Differential Effects of Bucindolol and Carvedilol on Noradenaline-Induced Hypertrophic Response in Ventricular Cardiomyocytes of Adult Rats

2002 ◽  
Vol 301 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Klaus Pönicke ◽  
Ingrid Heinroth-Hoffmann ◽  
Otto-Erich Brodde
Keyword(s):  
Adult Rats ◽  
Differential Effects ◽  
Hypertrophic Response ◽  
Ventricular Cardiomyocytes

Early increase in pulsatile growth hormone release after unilateral nephrectomy in adult rats

1994 ◽  
Vol 266 (4) ◽  
pp. F628-F632 ◽  
Author(s):  
A. Haramati ◽  
M. D. Lumpkin ◽  
S. E. Mulroney
Keyword(s):  
Growth Hormone ◽  
Early Time ◽  
Peak Level ◽  
Unilateral Nephrectomy ◽  
Sham Operation ◽  
Renal Growth ◽  
Adult Rats ◽  
Compensatory Renal Growth ◽  
Jugular Veins ◽  
Hypertrophic Response

Removal of one kidney results, within days, in accelerated growth of the remaining kidney. However, the mechanisms that underlie this compensatory renal hypertrophic response, particularly in the early time period following nephrectomy, are not understood. In this study we tested the hypothesis that removal of one kidney leads to a change in the pulsatile release of growth hormone (GH), which facilitates compensatory renal growth. Adult Wistar rats were implanted with Silastic cannulas in jugular veins and underwent either unilateral nephrectomy (UNX) or sham operation. Plasma levels of GH were determined 24 and 48 h after sham operation or UNX. Blood samples were taken every 20 min over a 6-h period from conscious, unrestrained animals. Pulsatile GH release was markedly elevated 24 h after UNX in both the amplitude of the surges as well as in the duration of release. Peak GH levels after 24 h were three- to fourfold higher in UNX rats compared with sham controls (417 +/- 75 vs. 119 +/- 23 ng/ml, P < 0.05). However, this enhanced release of GH appeared to be of short duration and began declining by 48 h post-UNX (peak level of 227 +/- 37 ng/ml, P < 0.05 vs. both 24 h UNX and sham controls). To examine whether this rise in GH release post-UNX contributed to the compensatory renal growth, rats underwent UNX and were immediately treated with an antagonist to GH-releasing factor (GRF-AN; i.e., [N-Ac-Tyr1,D-Arg2]GRF-(1-29) amide, 200 micrograms/kg twice daily), and the effects on GH release and renal growth were determined. Administration of GRF-AN significantly suppressed the increase in GH release post-UNX and was associated with a significant attenuation in renal growth 48 h post-UNX in GRF-AN-treated rats (8.7 +/- 2.6% vs. 22.7 +/- 3.0% in UNX controls, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Differential effects in male adult rats of lifelong coconut oil exposure versus during early-life only

2019 ◽  
Vol 55 ◽  
pp. 17-27 ◽  
Author(s):  
Fernanda Torres Quitete ◽  
Egberto Gaspar de Moura ◽  
Geórgia Correa Atella ◽  
Patricia Cristina Lisboa ◽  
Elaine de Oliveira
Keyword(s):  
Early Life ◽  
Coconut Oil ◽  
Adult Rats ◽  
Male Adult ◽  
Differential Effects ◽  
Oil Exposure

Differential effects of FSH and testosterone on the maintenance of spermatogenesis in the adult hypophysectomized rat

1989 ◽  
Vol 121 (1) ◽  
pp. 49-NP ◽  
Author(s):  
J. M. S. Bartlett ◽  
G. F. Weinbauer ◽  
E. Nieschlag
Keyword(s):  
Silicone Elastomer ◽  
Seminiferous Tubules ◽  
Adult Rats ◽  
Intact Control ◽  
Testosterone Treatment ◽  
Differential Effects ◽  
Adult Rat ◽  
Low Levels ◽  
Pachytene Spermatocytes

ABSTRACT In order to clarify further the role of FSH in the maintenance of spermatogenesis, adult rats were treated with purified human FSH (2 × 5 IU/day per rat), testosterone (1·5 cm silicone elastomer implant) or a combination of both hormones for 2 weeks following hypophysectomy. After hypophysectomy alone, no elongate spermatids were observed and the numbers of pachytene spermatocytes and round spermatids observed were reduced when compared with untreated controls. Testosterone supplementation alone qualitatively maintained the formation of elongate spermatids in most seminiferous tubules, whilst in FSH-treated rats increased numbers of round spermatids and pachytene spermatocytes were observed when compared with hypophysectomized animals. Formation of elongate spermatids, however, did not occur under FSH treatment alone. A combination of FSH and testosterone treatment maintained spermatogenesis in an almost quantitative fashion. Numbers of pachytene spermatocytes and round spermatids were maintained at about 80% of levels seen in intact control animals. Treatment with FSH or testosterone alone maintained testis weights at significantly higher levels than those seen in hypophysectomized controls (FSH, 0·79 ± 0·05 g; testosterone, 0·81 ± 0·07 g; hypophysectomized, 0·50 ± 0·04 g). Animals treated with FSH and testosterone showed testis weights 20% below control values (1·22 ± 0·05 vs 1·51 ± 0·06 g; P <0·05). No increases in intratesticular or intratubular androgen concentrations or in testosterone: dihydrotestosterone ratios were observed in any of the hormone-treated groups when compared with hypophysectomized controls. In all hypophysectomized animals testicular androgen concentrations were reduced to <5% of control values. The results obtained in this study suggest that FSH is involved in the maintenance of spermatogenesis in the adult rat and that the effects of FSH are not mediated through changes in intratesticular androgens. Low levels of testosterone in combination with FSH can almost quantitatively maintain spermatogenesis in adult rats. Journal of Endocrinology (1989) 121, 49–58

scholarly journals Differential effects of inhaled toluene on locomotor activity in adolescent and adult rats

2010 ◽  
Vol 96 (4) ◽  
pp. 438-448 ◽  
Author(s):  
Jeffery C. Batis ◽  
John H. Hannigan ◽  
Scott E. Bowen
Keyword(s):  
Locomotor Activity ◽  
Adult Rats ◽  
Differential Effects

scholarly journals Long-Term Oral Methylphenidate Treatment in Adolescent and Adult Rats: Differential Effects on Brain Morphology and Function

2013 ◽  
Vol 39 (2) ◽  
pp. 263-273 ◽  
Author(s):  
Kajo van der Marel ◽  
Anne Klomp ◽  
Gideon F Meerhoff ◽  
Pieter Schipper ◽  
Paul J Lucassen ◽  
...  
Keyword(s):  
Brain Morphology ◽  
Adult Rats ◽  
Differential Effects ◽  
And Function
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