Effects of selective sleep deprivation on sleep-linked prolactin and growth hormone secretion

Abstract

1. The secretion of prolactin and growth-hormone (hGH) was investigated during sleep in 10 healthy volunteers (8 males and 2 females): The comparison of one baseline night, one night after daytime physical exercise, and one night with selective deprivation of sleep stages 3 and 4 and paradoxical sleep showed clear differences of prolactin and hGH secretion during sleep. 2. Prolactin secretion is entrained into the sleep cycle of Non-REM and REM periods. A maximum of plasma hormone elevations occurs during the first quarter of sleep cycles, i.e., during Non-REM periods and less frequent rises at the end of the cycles, mainly during REM periods. 3. In contrast to growth hormone, concentrations of prolactin remain high also during later cycles occurring toward morning. This shows that high prolactin, but not high concentrations of hGH, regularly occur during sleep cycles with small amounts of slow-wave sleep. 4. Maximal prolactin concentrations during sleep are affected neither by preceding daytime physical exercise nor by selective deprivation of slow sleep stages 3 and 4. This is further evidence that slow-wave sleep stages are not necessary for the development of high plasma prolactin concentrations. However, peak values of growth hormone in the first and second cycle are significantly diminished after selective deprivation of sleep stages 3 and 4. 5. In abnormally long sleep cycles with artificial delay of the first REM period, the cyclical rhythmicity of prolactin release seems disturbed. This is further evidence for the sleep-dependent rhythmicity in the secretion of this hormone.

The Relationship between Episodic Variations of Plasma Prolactin and REM-Non-REM Cyclicity Is an Artifact*

“…This association between PRL nadirs and REM stages was confirmed in one subsequent study (2) but not in several others (3)(4)(5). Despite these conflicting reports and lack of detailed analysis, the concept of entrainment of episodic PRL release during sleep to REM-non-REM cyclicity became widely accepted (6)(7)(8).…”

Who are the long sleepers? Towards an understanding of the mortality relationship

“…Studies of endocrine function during sleep have suggested that long sleep periods are associated with disturbed prolactin rhythms 75 and that patients with growth hormone deficiencies show marked increases in total sleep time following treatment without increases in REM sleep 76 . It is unclear how these findings relate to the larger picture of sleep differences in long sleep, but reinforce the idea that changes in sleep duration are related to endocrine function, as noted in the aforementioned increased diabetes risk.…”

Effect of sleep deprivation on dopamine receptor function in normal subjects

“…Most such studies have focused on the effects of SD on sleep-induced GH and PRL secretion (Karacan et al, 1971;Sassin et aI., 1969;Jacoby et al, 1975;Beck and Marquetand, 1976). Little is known about the effect of SD on anterior pituitary secretion induced by other stimuli.…”