Differential effects of cannabinoid exposure and stress on plasma prolactin, growth hormone and corticosterone levels in male mice

Abstract

Plasma prolactin (PRL) levels were reduced in stressed and non-stressed male mice after a single dose of Δ 9-tetrahydrocannabinol (THC), the main psychoactive constituent of marihuana, while growth hormone (GH) levers were reduced only in non-stressed animals. Chronic treatment with THC did not affect PRL or GH levels under either condition. Neither acute nor repeated exposure to THC affected plasma corticosterone levels. In contrast to the affects of THC, acute exposure to cannabinol (CBN), a non-psychoactive ingredient in marihuana, increased plasma GH levels in non-stressed mice, while repeated CBN treatments reduced GH levels in stressed animals. Moreover, chronic CBN exposure resulted in decreased peripheral levels of corticosterone in both stressed and non-stressed mice, and reduced plasma PRL levels in stressed mice. Psychoactive and non-psychoactive components of marihuana can exert different effects on endocrine function and on responsivity to stress in male mice.