The effect of long-term treatment with deprenyl on basal and L-dopa evoked dopamine release in vitro from the corpus striatum of aged rats.
Male; Animals; Rats; Corpus Striatum/*drug effects/metabolism; Aging/metabolism; In Vitro Techniques; Dopamine/*metabolism; Amphetamine/pharmacology; Levodopa/pharmacology; Selegiline/*pharmacology; 3; 4-Dihydroxyphenylacetic Acid/*metabolism
In the present experiment, male rats (15-17 months) were injected with deprenyl (0.25 mg/kg) three times per week for six months. At 21-23 months of age the male rats were sacrificed, the corpus striatum removed and superfused in vitro. Basal and evoked dopamine and DOPAC levels, as obtained with either two infusions of
Dluzen D E; McDermott J L
Journal of neural transmission. General section
1991
1991
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1007/bf01244706" target="_blank" rel="noreferrer noopener">10.1007/bf01244706</a>
Inactivation of one copy of the mouse neurotrophin-3 gene induces cardiac sympathetic deficits.
*Gene Dosage; Aging/metabolism; Animals; Axons/metabolism; Body Weight/genetics; Cell Count; Coronary Vessels/innervation; Heart Rate/genetics; Heart/*innervation; Heterozygote; Homozygote; In Situ Nick-End Labeling; Knockout; Mice; Muscle Tonus/genetics; Mutant Strains; Myocardium/cytology/*metabolism; Neurotrophin 3/deficiency/*genetics; Norepinephrine/metabolism; Organ Size/genetics; Stellate Ganglion/cytology; Sympathetic Nervous System/cytology/*growth & development/metabolism; Tyrosine 3-Monooxygenase/metabolism
Whether two copies of the neurotrophin-3 (NT3) gene are necessary for proper development of cardiac sympathetic innervation was investigated in mice carrying a targeted inactivation of the NT3 gene. Heterozygous (+/-) and null (-/-) mutant mice had fewer stellate ganglion neurons than did wild-type (+/+) mice at postnatal day 0 (P0 or birth), and this deficit was maintained between adult (P60) +/- and +/+ mice. The sympathetic innervation of the heart matured postnatally in +/+ and +/- mice. Tyrosine hydroxylase (TH)-positive axons were restricted largely to the epicardium at P0, were concentrated around large blood vessels in the myocardium at P21, and were present among cardiac myocytes at P60. Cardiac norepinephrine (NE) concentrations paralleled the growth of the sympathetic axons into the heart. NE concentrations were equivalent among +/+, +/-, and -/- mice at birth, but differences between +/- and +/+ mice increased with age. Adult +/- mice also exhibited lower resting heart rates and sympathetic tonus than +/+ mice. Thus deletion of one copy of the NT3 gene translates into anatomical, biochemical, and functional deficits in cardiac sympathetic innervation of postnatal mice, thereby indicating a gene-dosage effect for the NT3 gene.
Story G M; DiCarlo S E; Rodenbaugh D W; Dluzen D E; Kucera J; Maron M B; Walro J M
Physiological genomics
2000
2000-04
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1152/physiolgenomics.2000.2.3.129" target="_blank" rel="noreferrer noopener">10.1152/physiolgenomics.2000.2.3.129</a>
Distal air space epithelial fluid clearance in near-term rat fetuses is fast and requires endogenous catecholamines.
Adrenergic beta-Antagonists/pharmacology; Aging/metabolism; Animals; Body Fluids/*metabolism; Body Water/metabolism; Catecholamines/*physiology; Embryonic and Fetal Development; Epinephrine/blood; Epithelium/metabolism; Female; Fetus/drug effects/metabolism; Gestational Age; Lung/drug effects/*embryology/metabolism; Male; Newborn/metabolism; Propranolol/pharmacology; Rats; Sprague-Dawley; Time Factors
Knowledge about the conversion of the epithelium in the distal air spaces of the lung from secretion to absorption is imperative to the understanding of postnatal lung development; little such information is available in rats. Distal air space fluid clearance was therefore measured in 21- to 22-day gestation rat fetuses and newborn (40 h) rats. Distal air space fluid clearance was measured from the increase in (131)I-albumin concentration in an isosmolar, physiological solution instilled into the developing lungs. There was no net fluid movement across the distal air space epithelium in the lungs of 21-day gestation fetuses. Twenty-four hours later, distal air space fluid was cleared at a rapid rate in the 22-day gestation fetuses. Within the first 40 h after birth, the rate rapidly declined to adult levels. The high distal air space fluid clearance at 22 days gestation and at 40 h after birth was mediated by beta-adrenergic receptors as demonstrated by elevated plasma epinephrine levels and inhibition by propranolol. Interestingly, the elevated distal air space fluid clearance in the 22-day gestation fetuses was only minimally amiloride sensitive; however, amiloride sensitivity increased over the first 40 h after birth. In conclusion, these studies demonstrate that 1) rapid rates of net alveolar fluid clearance occur late in gestation in the rat and 2) this clearance is driven by elevations of endogenous epinephrine.
Folkesson Hans G; Matthay Michael A; Chapin Cheryl J; Porta Nicolas F M; Kitterman Joseph A
American journal of physiology. Lung cellular and molecular physiology
2002
2002-03
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1152/ajplung.00183.2001" target="_blank" rel="noreferrer noopener">10.1152/ajplung.00183.2001</a>
Why adult mammalian intrafusal and extrafusal fibers contain different myosin heavy-chain isoforms.
*Muscle Development; Afferent Pathways/physiology; Aging/metabolism; Animals; Cell Lineage; Developmental; Fetal Proteins/metabolism; Gene Expression Regulation; Knockout; Mammals/anatomy & histology/*metabolism; Mice; Morphogenesis; Muscle; Muscle Contraction; Muscle Fibers; Muscle Proteins/deficiency/physiology; Muscle Spindles/physiology; Myosin Heavy Chains/*metabolism; Nerve Tissue Proteins/deficiency/physiology; Protein Isoforms/*metabolism; Rats; Skeletal/*chemistry/classification; Skeletal/chemistry/embryology/*growth & development/ultrastructure; Transgenic
Multiple isoforms of the contractile protein myosin are present in mammalian skeletal muscles. The diversity of the heavy-chain subunits of myosin (MyHCs) in intrafusal fibers is thought to reflect a pathway of differentiation that is unique to muscle spindles. In fact, intrafusal MyHCs are developmental isoforms expressed by the prenatal precursors of both intrafusal and extrafusal fibers. In adult limbs, developmental MyHCs persist in intrafusal, but not extrafusal fibers principally due to the afferent neurons that arrest their maturational replacement by MyHCs associated with faster shortening velocities. The slow shortening velocities that are characteristic of developmental MyHCs might be adaptive for precise calibration of muscle spindles as sense organs.
Walro J M; Kucera J
Trends in neurosciences
1999
1999-04
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/s0166-2236(98)01339-3" target="_blank" rel="noreferrer noopener">10.1016/s0166-2236(98)01339-3</a>
The versatility and paradox of GDF 11.
Aging; Aging/metabolism; Animals; Biomarker; Biomarkers/metabolism; BMP signaling; Bone Morphogenetic Proteins/*metabolism; Development; Embryonic Development; Erythropoiesis; Growth differentiation factor 11; Growth Differentiation Factors/*metabolism; Humans; Neurogenesis; Pancreas/growth & development/metabolism; Retina/growth & development/metabolism
In addition to its roles in embryonic development, Growth and Differentiation Factor 11 (GDF 11) has recently drawn much interest about its roles in other processes, such as aging. GDF 11 has been shown to play pivotal roles in the rescue of the proliferative and regenerative capabilities of skeletal muscle, neural stem cells and cardiomyocytes. We would be remiss not to point that some controversy exists regarding the role of GDF 11 in biological processes and whether it will serve as a therapeutic agent. The latest studies have shown that the level of circulating GDF 11 correlates with the outcomes of patients with cardiovascular diseases, cancer and uremia. Based on these studies, GDF 11 is a promising candidate to serve as a novel biomarker of diseases. This brief review gives a detailed and concise view of the regulation and functions of GDF 11 and its roles in development, neurogenesis and erythropoiesis as well as the prospect of using this protein as an indicator of cardiac health and aging.
Jamaiyar A; Wan W; Janota D M; Enrick M K; Chilian W M; Yin L
Pharmacology & therapeutics
2017
2017-07
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/j.pharmthera.2017.02.032" target="_blank" rel="noreferrer noopener">10.1016/j.pharmthera.2017.02.032</a>
Effects of neonatal and prepubertal hormonal manipulations upon estrogen neuroprotection of the nigrostriatal dopaminergic system within female and male mice.
*Sex Characteristics; Aging/metabolism; Animal; Animals; Disease Models; Dopamine/metabolism; Estrogens/metabolism/*pharmacology; Female; Gonads/growth & development/metabolism; Male; Methamphetamine/antagonists & inhibitors/toxicity; Mice; Neostriatum/*drug effects/metabolism/physiopathology; Neural Pathways/drug effects/metabolism/physiopathology; Neuroprotective Agents/metabolism/*pharmacology; Newborn; Orchiectomy; Ovariectomy; Sexual Maturation/physiology; Substantia Nigra/*drug effects/metabolism/physiopathology; Testosterone/metabolism/*pharmacology
Estrogen (E) can function as a neuroprotectant of the nigrostriatal dopaminergic (NSDA) system against methamphetamine (MA) neurotoxicity in female, but not male, mice. In the present report we examined whether the organizational effects of gonadal steroid hormones, as exerted in the early postnatal period, or developmental effects, as exerted during the pubertal period, would contribute to this sexually dimorphic neuroprotectant action of E. Neonatal gonadectomy and treatment with testosterone of female mice, retained the ability to show an E neuroprotectant response when tested as adults. However, females not treated with gonadal steroids failed to show an E-dependent neuroprotectant response. Neonatal gonadectomy of male mice, failed to result in the display of an E neuroprotectant response when tested as adults. Prepubertal gonadectomy of female mice, with or without testosterone treatment, abolished the capacity for E to produce neuroprotection against MA-induced NSDA neurotoxicity. Nor did prepubertal gonadectomy enable male mice to show an E neuroprotectant response. Taken together these results demonstrate that none of the manipulations performed within male mice enabled them to show an E-dependent neuroprotective response against MA-induced neurotoxicity of the NSDA system when tested as adults. For the female, it appears that the presences of gonadal steroids at these two developmental periods are needed for the display of an E-dependent neuroprotectant response within the adult.
Anderson L I; Leipheimer R E; Dluzen D E
Neuroscience
2005
1905-06
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/j.neuroscience.2004.09.033" target="_blank" rel="noreferrer noopener">10.1016/j.neuroscience.2004.09.033</a>
Beyond thermoregulation: metabolic function of cetacean blubber in migrating bowhead and beluga whales.
*Lipid Metabolism; Adipose Tissue/*metabolism; Aging/metabolism; Amino Acid Sequence; Animals; Base Sequence; Beluga Whale/*physiology; Blubber; Body Temperature Regulation; Bowhead whale; Bowhead Whale/*physiology; Development; Female; Humans; Inbred C57BL; Leptin; Leptin/genetics; Leptin/genetics/metabolism; Lipase/genetics; Long-Evans; Male; Metabolic activity; Mice; Rats; Receptors; Seasons
The processes of lipid deposition and utilization, via the gene leptin (Lep), are poorly understood in taxa with varying degrees of adipose storage. This study examines how these systems may have adapted in marine aquatic environments inhabited by cetaceans. Bowhead (Balaena mysticetus) and beluga whales (Delphinapterus leucas) are ideal study animals-they possess large subcutaneous adipose stores (blubber) and undergo bi-annual migrations concurrent with variations in food availability. To answer long-standing questions regarding how (or if) energy and lipid utilization adapted to aquatic stressors, we quantified variations in gene transcripts critical to lipid metabolism related to season, age, and blubber depth. We predicted leptin tertiary structure conservation and assessed inter-specific variations in Lep transcript numbers between bowheads and other mammals. Our study is the first to identify seasonal and age-related variations in Lep and lipolysis in these cetaceans. While Lep transcripts and protein oscillate with season in adult bowheads reminiscent of hibernating mammals, transcript levels reach up to 10 times higher in bowheads than any other mammal. Data from immature bowheads are consistent with the hypothesis that short baleen inhibits efficient feeding. Lipolysis transcripts also indicate young Fall bowheads and those sampled during Spring months limit energy utilization. These novel data from rarely examined species expand the existing knowledge and offer unique insight into how the regulation of Lep and lipolysis has adapted to permit seasonal deposition and maintain vital blubber stores.
Ball H C; Londraville R L; Prokop J W; George John C; Suydam R S; Vinyard C; Thewissen J G M; Duff R J
Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology
2017
2017-01
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1007/s00360-016-1029-6" target="_blank" rel="noreferrer noopener">10.1007/s00360-016-1029-6</a>