Lithium: Short-term and chronic effects on plasma testosterone and luteinizing hormone concentrations in mice

SUMMARY Plasma luteinizing hormone (LH) levels and LH responses to intravenous administration of 100 μg luteinizing hormone releasing hormone (LH-RH) were studied in entire rams, long-term castrated animals (operation performed six months previously), long-term castrated animals treated with testosterone for the two preceding weeks and short-term castrated animals (castrated 3 h before LH-RH injection). LH was measured by radioimmunoassay in samples taken at 5 or 15 min intervals. Basal LH levels were lower in entire rams (0·9 ng/ml) than in long-term castrated animals (6·0 ng/ml). After LH-RH treatment the LH response was much smaller (peak level 9·6 ng/ml, total response 13·3 ng/ml/1 h) and slower (120 min to peak) in entire than in long-term castrated animals (peak level 61·8 ng/ml, total response 141·2 ng/ml/1 h, 29 min to peak). Testosterone treatment after long-term castration depressed the basal LH level and delayed the peak LH response after LH-RH to values similar to those for entire rams. After short-term castration the response to LH-RH was already as great (peak level 70·1 ng/ml, total response 133·6 ng/ml/1 h) as after long-term castration. The latency to peak LH level (82 min) was intermediate between that for untreated and testosterone-treated long-term castrated animals (130 min). Testosterone treatment was considered to have acted on the hypothalamus to depress basal levels. The results provided evidence for the presence of two inhibitory actions of the testis at the pituitary level in the ram: a qualitative delaying action of testosterone and a quantitative inhibitory action of the testis on LH release after LH-RH injection. The latter may also be related to plasma testosterone levels.

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Short-term and chronic effects of transdermal nitroglycerin in stable angina pectoris

Drug Development Research ◽

10.1002/ddr.430090306 ◽

1986 ◽

Vol 9 (3) ◽

pp. 219-224 ◽

Cited By ~ 3

Author(s):

Kenneth W. Hunter ◽

Rajat Mahapatra

Keyword(s):

Angina Pectoris ◽

Stable Angina ◽

Stable Angina Pectoris ◽

Short Term ◽

Chronic Effects

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Short Term Variation in Serum Luteinizing Hormone and Testosterone in the Male Japanese Quail

Poultry Science ◽

10.3382/ps.0620908 ◽

1983 ◽

Vol 62 (5) ◽

pp. 908-913 ◽

Cited By ~ 8

Author(s):

M.A. OTTINGER

Keyword(s):

Luteinizing Hormone ◽

Japanese Quail ◽

Short Term ◽

Serum Luteinizing Hormone ◽

Term Variation

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Use of GnRH for Synchronization of the Follicular Wave in Assisted Reproductive Technologies in Sheep: A Preliminary Study

Animals ◽

10.3390/ani10071208 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1208

Author(s):

Aina Año-Perello ◽

Zurisaday Santos-Jimenez ◽

Teresa Encinas ◽

Paula Martinez-Ros ◽

Antonio Gonzalez-Bulnes

Keyword(s):

Luteinizing Hormone ◽

Assisted Reproductive Technologies ◽

Ovarian Response ◽

Reproductive Technologies ◽

Estrus Synchronization ◽

Short Term ◽

Follicular Wave ◽

Preliminary Study ◽

Cost Efficient ◽

Set Up

The present study aimed to set up a short-term protocol for synchronization of follicular wave emergence in sheep, concomitant with estrus synchronization, which would improve ovarian response in assisted reproductive technologies. Administration of a single GnRH dose, concomitant with the insertion of a progesterone-loaded CIDR device, caused regression of gonadotrophin-dependent follicles ≥4 mm in all the GnRH-treated sheep and in around 80% of the controls treated only with CIDR (p < 0.05). Similar percentages of ewes lost all follicles (around 70%) or only the largest one (around 30%) in both groups. Hence, 54.1% and 70% of the sheep lost all large follicles and initiated a new follicular wave in the control and GnRH groups, respectively (p < 0.05). The remaining sheep showed follicles that were still not dependent of luteinizing hormone (LH). So, in fact, all the sheep had non-dominant follicles after treatment. In conclusion, a treatment including GnRH at CIDR insertion would offer a time- and cost-efficient protocol for inducing follicular turnover and synchronizing a new follicular wave at any stage of the estrous cycle.

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A toxicological investigation of some acute, short-term, and chronic effects of administering di-2-ethylhexyl phthalate (DEHP) and other phthalate esters

Environmental Research ◽

10.1016/0013-9351(75)90043-2 ◽

1975 ◽

Vol 9 (1) ◽

pp. 1-11 ◽

Cited By ~ 58

Author(s):

W.H. Lawrence ◽

M. Malik ◽

J.E. Turner ◽

A.R. Singh ◽

J. Autian

Keyword(s):

Phthalate Esters ◽

Short Term ◽

Chronic Effects ◽

Toxicological Investigation ◽

Ethylhexyl Phthalate

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Plasma Testosterone, Luteinizing Hormone and Follicle-Stimulating Hormone one Day after Vasectomy

Andrologia ◽

10.1111/j.1439-0272.1979.tb02208.x ◽

2009 ◽

Vol 11 (4) ◽

pp. 294-296 ◽

Cited By ~ 1

Author(s):

R.E. JOHNSONBAUGH ◽

L.P. GEORGES ◽

C.L. CZERWINSKI ◽

M. EDSON

Keyword(s):

Luteinizing Hormone ◽

Follicle Stimulating Hormone ◽

Plasma Testosterone ◽

Stimulating Hormone

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Plasma testosterone surge and luteinizing hormone beta (LH-β) following parturition: lack of association in the male rat

Acta Endocrinologica ◽

10.1530/eje.0.1330366 ◽

1995 ◽

Vol 133 (3) ◽

pp. 366-374 ◽

Cited By ~ 8

Author(s):

Robert F McGivern ◽

Ralph HM Hermans ◽

Robert J Handa ◽

Lawrence D Longo

Keyword(s):

Luteinizing Hormone ◽

Cesarean Section ◽

Gnrh Antagonist ◽

Male Rat ◽

Plasma Testosterone ◽

Treatment Groups ◽

Natural Birth ◽

Males And Females ◽

Lh Secretion

McGivern RF, Hermans RHM, Handa RJ, Longo LD. Plasma testosterone surge and luteinizing hormone beta (LH-β) following parturition: lack of association in the male rat. Eur J Endocrinol 1995; 133:366–74. ISSN 0804–4643 Studies examining the role of luteinizing hormone (LH) in the initiation of the postnatal surge of testosterone in the male rat have produced ambiguous results. We examined the pattern of postnatal LH secretion in the newborn male rat, coincident with plasma testosterone levels, using a specific monoclonal antibody for LH-β. In some males, we attempted to block LH secretion and the postnatal testosterone surge by injecting males with a gonadotropin-releasing hormone (GnRH) antagonist, an LH antibody or progesterone immediately after delivery by cesarean section on day 22. Following injection, animals were immediately sacrificed (time 0) or housed in a humidified incubator maintained at 30°C until sacrifice at 60, 120, 240, 360 or 480 min after delivery. Plasma from individual animals was measured subsequently for LH-β and testosterone by radioimmunoassay. Results revealed a postnatal surge of testosterone which peaked at 2 h after delivery in males from all treatment groups. This testosterone surge was not accompanied by a postnatal rise in plasma LH-β in any group. Administration of the GnRH antagonist or the ethanol vehicle produced a transient drop of approximately 25% in LH-β levels at 60 min but did not decrease the postnatal testosterone surge in the same animals. Additional studies in untreated males and females born by cesarean section or natural birth also failed to reveal a postnatal rise in plasma LH-β during the first 3 h after birth. Plasma levels in both sexes were significantly lower in animals delivered by cesarean section compared to natural birth. Overall, these results indicate that the postnatal surge of testosterone occurs without a corresponding surge of detectable LH-β in the male rat. Robert F McGivern, 6363 Alvarado Ct, Suite 200H. San Diego, CA 92120, USA

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SHORT-TERM EFFECTS OF COPULATION, HUMAN CHORIONIC GONADOTROPHIN INJECTION AND NON-TACTILE ASSOCIATION WITH A FEMALE ON TESTOSTERONE LEVELS IN THE MALE RAT

Journal of Endocrinology ◽

10.1677/joe.0.0600429 ◽

1974 ◽

Vol 60 (3) ◽

pp. 429-439 ◽

Cited By ~ 61

Author(s):

K. PURVIS ◽

N. B. HAYNES

Keyword(s):

Chorionic Gonadotrophin ◽

Human Chorionic Gonadotrophin ◽

Physical Contact ◽

Male Rats ◽

Male Rat ◽

Plasma Testosterone ◽

Short Term ◽

Testosterone Levels ◽

Peripheral Plasma ◽

First Contact

SUMMARY Peripheral plasma testosterone levels in the male rat were increased above control levels 5 min after the first intromission with an oestrous female, or 8–10 min after first contact with the female. The levels remained raised for at least 30 min if copulation was allowed to continue. Intravenous injection of human chorionic gonadotrophin resulted in an increased peripheral concentration of plasma testosterone after 10–15 min and an increase of testosterone content of the testis 5–10 min after injection, indicating that the rat testis has a potential to respond rapidly to gonadotrophin. The results suggested that if the testosterone surge during copulation was gonadotrophin-dependent, it was initiated before the first intromission. Indeed, plasma testosterone levels were raised in male rats 5 min after being placed in the proximity of oestrous females but not allowed physical contact.

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