scholarly journals A new thienopyrimidine-based allosteric regulator of lutheinizing hormone receptor and its unexpected inverse agonist effects on testosterone production in male rats

2021 ◽  
Author(s):  
Andrey Bakhtyukov ◽  
Anna Stepochkina ◽  
Kira Derkach ◽  
Viktor Sorokoumov ◽  
Ekaterina Fokina ◽  
...  
Keyword(s):  
Hormone Receptor ◽  
Inverse Agonist ◽  
Male Rats ◽  
Testosterone Production ◽  
Allosteric Regulator

Decrease in the Basal and Luteinizing Hormone Receptor Agonist–Stimulated Testosterone Production in Aging Male Rats

2019 ◽  
Vol 9 (2) ◽  
pp. 179-185 ◽  
Author(s):  
A. A. Bakhtyukov ◽  
K. V. Derkach ◽  
D. V. Dar’in ◽  
T. S. Sharova ◽  
A. O. Shpakov
Keyword(s):  
Luteinizing Hormone ◽  
Hormone Receptor ◽  
Receptor Agonist ◽  
Luteinizing Hormone Receptor ◽  
Male Rats ◽  
Aging Male ◽  
Testosterone Production

Effects of hypoxia on testosterone release in rat Leydig cells

2009 ◽  
Vol 297 (5) ◽  
pp. E1039-E1045 ◽  
Author(s):  
Guey-Shyang Hwang ◽  
Szu-Tah Chen ◽  
Te-Jung Chen ◽  
Shyi-Wu Wang
Keyword(s):  
Calcium Channel ◽  
Adenylyl Cyclase ◽  
Intermittent Hypoxia ◽  
Leydig Cells ◽  
Channel Blocker ◽  
Male Rats ◽  
Plasma Testosterone ◽  
Testosterone Production

The aim of this study was to explore the effect and action mechanisms of intermittent hypoxia on the production of testosterone both in vivo and in vitro. Male rats were housed in a hypoxic chamber (12% O2 + 88% N2, 1.5 l/ml) 8 h/day for 4 days. Normoxic rats were used as control. In an in vivo experiment, hypoxic and normoxic rats were euthanized and the blood samples collected. In the in vitro experiment, the enzymatically dispersed rat Leydig cells were prepared and challenged with forskolin (an adenylyl cyclase activator, 10−4 M), 8-Br-cAMP (a membrane-permeable analog of cAMP, 10−4 M), hCG (0.05 IU), the precursors of the biosynthesis testosterone, including 25-OH-C (10−5 M), pregnenolone (10−7 M), progesterone (10−7 M), 17-OH-progesterone (10−7 M), and androstendione (10−7-10−5 M), nifedipine (L-type Ca2+ channel blocker, 10−6-10−4 M), nimodipine (L-type Ca2+ channel blocker, 10−5 M), tetrandrine (L-type Ca2+ channel blocker, 10−5 M), and NAADP (calcium-signaling messenger causing release of calcium from intracellular stores, 10−6-10−4 M). The concentrations of testosterone in plasma and medium were measured by radioimmunoassay. The level of plasma testosterone in hypoxic rats was higher than that in normoxic rats. Enhanced testosterone production was observed in rat Leydig cells treated with hCG, 8-Br-cAMP, or forskolin in both normoxic and hypoxic conditions. Intermittent hypoxia resulted in a further increase of testosterone production in response to the testosterone precursors. The activity of 17β-hydroxysteroid dehydrogenase was stimulated by the treatment of intermittent hypoxia in vitro. The intermittent hypoxia-induced higher production of testosterone was accompanied with the influx of calcium via L-type calcium channel and the increase of intracellular calcium via the mechanism of calcium mobilization. These results suggested that the intermittent hypoxia stimulated the secretion of testosterone at least in part via stimulatory actions on the activities of adenylyl cyclase, cAMP, L-type calcium channel, and steroidogenic enzymes.

Oestrogenic regulation of testicular androgen production during development in the rat

1985 ◽  
Vol 105 (2) ◽  
pp. 211-218 ◽  
Author(s):  
B. A. Keel ◽  
T. O. Abney
Keyword(s):  
Serum Testosterone ◽  
Male Rats ◽  
Serum Prolactin ◽  
Testicular Function ◽  
Intact Male ◽  
Oestrogen Treatment ◽  
Testosterone Production ◽  
Age Related ◽  
Serum Lh

ABSTRACT The influence of age on the sensitivity of the testis to oestrogens was investigated. Intact male rats at 10, 25, 40 and 53 days of age were injected s.c. with vehicle, 5 or 50 μg oestradiol or diethylstilboestrol (DES)/100 g body wt twice daily for 2 days; the animals were killed 12 h after the last injection. Subsequently, the concentrations of testicular androgens and serum LH, prolactin, testosterone and androstanediol (5α-androstane-3α, 17β-diol) were measured. Testicular androgen production was determined in vitro in the presence or absence of human chorionic gonadotrophin (hCG) or dibutyryl cyclic AMP (dbcAMP). Androgens in the serum and testes displayed an age-related alternating pattern with androstanediol being the major androgen produced at 27 days of age. As a result of oestrogen treatment, serum LH concentrations were decreased while serum prolactin was increased. Serum testosterone was decreased by 36–55% in the 12-day-old group and further reduced by 95% of control values by day 55; serum androstanediol was less sensitive to oestrogen suppression. Testicular concentrations of both testosterone and androstanediol exhibited a marked reduction in 12-day-old animals as a result of oestrogen administration. These values were reduced by 85–95% at day 27 and remained suppressed even at 55 days. Basal production of testosterone was unaffected by oestrogen treatment in 12- and 27-day-old animals but was markedly decreased by day 42. Significant suppression of basal production of androstanediol was observed as early as day 12. Oestradiol treatment caused a significant reduction in hCG responsiveness of both androgens at days 12, 42 and 55. Oestrogen administration resulted in a significant (32–59%) decline in dbcAMP-responsive testosterone production in the 42-day group and a further suppression in the 55-day group. A marked inhibition of dbcAMP-stimulated androstanediol production was also observed in the 42- and 55-day groups. Testosterone production in response to dbcAMP was not significantly altered in the 12- and 27-day groups. With few exceptions the effects of oestradiol and DES on testicular function were similar. The data presented here suggest that the inhibitory effects of oestrogens become more pronounced as the animal approaches adulthood, that oestradiol and DES are similarly effective in regulating testicular function at all ages studied and that the production of both testosterone and androstanediol are suppressed by oestrogen administration. J. Endocr. (1985) 105, 211–218

Hachimijiogan Produces Testosterone in Adult Rat Testes

1988 ◽  
Vol 16 (03n04) ◽  
pp. 93-105 ◽  
Author(s):  
Satoshi Usuki
Keyword(s):  
Male Rats ◽  
In Vivo Study ◽  
Steroid Production ◽  
Adult Rat ◽  
Testosterone Production ◽  
Incubation Study ◽  
Estradiol 17Β

The effect of Hachimijiogan (HZ) and Keishibukuryogan (KB) on the steroid production in rats was examined in vivo and in vitro. In an in vivo study, HZ stimulated the testes from ten-week old male rats to produce testoterone, whereas KB decreased the tissue testosterone concentrations. The Δ4-androstenedione and estradiol-17β (E2) showed no significant changes. In an incubation study, HZ also stimulated the testosterone production. The data suggested that HZ produces testosterone in rat testes. The role of KB is questionable.

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