The Opioid Control of Lh and FSH Release: Effects of a Met‐enkephalin Analogue and Naloxone

Grossman, Ashley; Moult, P. J. A.; Gaillard, R. C.; Delitala, G.; Toff, William D.; Rees, Lesley; Besser, G. M.

doi:10.1111/j.1365-2265.1981.tb00363.x

Cited by 172 publications

(52 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The delayed time of onset was not unexpected since endocrine studies with DAMME in another laboratory showed a maximum effect of luteinizing hormone release at 180 minutes 19 while naloxone has its greatest effect both on prolactin release 20 and blood pressure during sleep 5 at this same time. The reason for this delay is not clear.…”

Section: Discussionmentioning

confidence: 92%

Endogenous opioids and baroreflex control in humans.

Pc¹,

McLean²,

Reid³

1983

Hypertension

View full text Add to dashboard Cite

SUMMARY We describe two studies designed to elucidate the role of endogenous opioids in blood pressure control in humans. In the first study, nine normal subjects received infusions of DAMME (a metenkephalin analog), naloxone, or saline, and blood pressure, heart rate, and plasma norepinephrine concentration were determined supine and following 5 minutes of 70° head-up tilt at intervals for 6 hours. Blood pressure following tilt was significantly decreased by DAMME but not influenced by naloxone, the effect being most marked at 3 hours (placebo = 110 ± 6/78 ± 7 mm Hg; naloxone = 106 ± 10/79 ± 5 mm Hg; DAMME = 96 ± 16/67 ± 8 mm Hg (p < 0.01). However, heart rate and plasma norepinephrine did not rise in response to this hypotension. Heart rates at 3 hours were: placebo = 87 ± 16 bpm; naloxone = 88 ± 19 bpm; DAMME = 89 ± 23 bpm. Plasma norepinephrine levels (nmol/ liter) at 3 hours were: placebo = 6.0 ± 2.2; naloxone = 5.8 ± 1.9; DAMME = 6.0 ± 1.9. In the second study, seven normal subjects had blood pressure reduced by incremental infusions of sodium nitroprusside, and the effects of placebo, naloxone, and DAMME on the slope of the heart period/ blood pressure relationship investigated. Naloxone significantly increased the slope by 90% and DAMME significantly reduced the slope by 30%. It is concluded that endogenous opioids modulate the baroreflex control of blood pressure in normal humans. (Hypertension 5: 535-538, 1983) KEY WORDS • enkephalin • DAMME • naloxone • blood pressure E NDOGENOUS opioids may participate in circulatory control. Administration of synthetic opioid pentapeptides to the cisterna magna of dogs produces a fall in blood pressure.1 The specific opiate receptor antagonist, naloxone, reverses the fall in blood pressure associated with both endotoxic and hypovolemic shock in rats, 2 -3 and preliminary data suggest similar findings in humans. 4 A physiological role for opioids in blood pressure control is suggested by the observation that naloxone prevents the fall in blood pressure in humans that normally occurs during sleep.5 A possible site of opioid action is in the brain stem at primary baroreceptor synapses in the nucleus of the solitary tract. This area is known to have a high concentration of opioid containing fibers and opiate receptors.6 -7 In dogs and rabbits, the circulatory reflex responses to both pressor and depressor stimuli are attenuated by morphine or opioid analogs and potentiated by naloxone. 89 We have studied the influence on circulatory control in humans of a metenkephalin analog and of naloxone. Our findings suggest that the endogenous opioids modulate baroreflex function in humans.From the University Department of Materia Medica, Stobhill General Hospital, Glasgow Scotland.This study was supported by British Heart Foundation Grant 80/ 85.Address for reprints: Dr. Peter Rubin, University Department of Materia Medica, Stobhill General Hospital, Glasgow G21 3UW, Scotland.Received August 27, 1982; revision accepted December 6, 1982. MethodsThe study was performed in two p...

show abstract

Section: Discussionmentioning

confidence: 92%

Endogenous opioids and baroreflex control in humans.

Pc¹,

McLean²,

Reid³

1983

Hypertension

View full text Add to dashboard Cite

show abstract

“…Natural endogenous opioid peptides have been implicated in the suppression of hypothalamic GnRH (Grossman et al 1981). The use of naloxone (an opiate receptor blocker) stimulates the secretion of LH in women that have previously experienced hypothalamic amenorrhea.…”

Section: Discussionmentioning

confidence: 99%

LH responses to single doses of exogenous GnRH by social Mashona mole–rats:a continuum of socially induced infertility in the family Bathyergidae

Bennett

Faulkes

Spinks

1997

Proc. R. Soc. Lond. B

View full text Add to dashboard Cite

SUMMARYThe Mashona mole-rat, Cryptomys darlingi, exhibits an extreme reproductive division of labour. Reproduction in the colony is restricted to a single breeding pair. The non-reproductive male and female colony members are restrained from sexual activity by being familiar and related to one another and the reproductive animals.Circulating basal concentrations of luteinizing hormone (LH) as well as LH levels measured in response to a single exogenous gonadotropin releasing hormone (GnRH) challenge are not significantly different between the reproductive and non-reproductive groups of either sex. Socially induced infertility in both non-reproductive males and females does not result from a reduced pituitary secretion of LH or decreased sensitivity to hypothalamic GnRH, but rather appears to result from an inhibition of reproductive behaviour in these obligate outbreeders.The African mole-rats exhibit a continuum of socially induced infertility with differing social species inhabiting regions of varying degrees of aridity. In this continuum a transition from a predominantly behavioural repression in a social mesic-adapted species through to complete physiological suppression lacking incest avoidance in an arid-adapted eusocial species occurs in this endemic African family of rodents.

show abstract

“…Recently it has been found that enkephalins decrease LH and FSH levels, affecting also adenohypo physial and other hormones [8]. This effect may be transmitted via the involvement of the opiate receptors [9]. All these data suggest that testosterone administration might be ef fective in patients suffering from CH, for one can suppose that artificial augmentation of this hormone's concentration would inhibit pain reaction.…”

mentioning

confidence: 99%

Use of Testosterone in the Treatment of Cluster Headache

Klimek¹

1985

Eur Neurol

View full text Add to dashboard Cite

The study was carried out on 15 men suffering from the episodic form (12 patients) and the chronic one (3 patients) of cluster headache. Before treatment the patients did not receive any drugs, and after determining the index of attacks the treatment was commenced. For 7–10 days patients were given testosteronum propionicum (25 mg) once a day intramuscularly, and then for the same period of time testosterone (10 mg). Before treatment the index of attacks was 3.66 (total number of attacks 308). In the 1st week of treatment the index decreased to 1.11 (total number of attacks 94) and to 0.16 in the 2nd week. In 3 patients with the chronic form of cluster headache testosterone was ineffective.

show abstract

The Opioid Control of Lh and FSH Release: Effects of a Met‐enkephalin Analogue and Naloxone

Cited by 172 publications

References 13 publications

Endogenous opioids and baroreflex control in humans.

Endogenous opioids and baroreflex control in humans.

LH responses to single doses of exogenous GnRH by social Mashona mole–rats:a continuum of socially induced infertility in the family Bathyergidae

Use of Testosterone in the Treatment of Cluster Headache

Contact Info

Product

Resources

About