A Study on the Effects of Stress of Pain and Ethanol on the Reproductive Function and Beta-endorphin Release in Mature Female Albino Rats and Their Offspring

The present work was performed to investigate the effect of acute and chronic stress
of pain and ethanol on the reproductive function, hormonal response and βendorphin
release in non pregnant, and pregnant female albino rats and their offspring. This
study was performed on 60 mature female albino rats divided into two groups, non
pregnant group and pregnant group, each group is subdivided into 3 groups: 1-Control group 2- Acute stress group in which the rats were exposed to stress of pain
for one hour or ethanol injection 3-Chronic group in which the rats were exposed to
stress of pain for one hour or ethanol injection daily for one week. The pregnant
group was subdivided in the same manner into three groups, and the resulted
neonates were divided according their mothers into three groups. At the end of
experiment, the normal rats and neonates of pregnant rats were decapitated, and
blood samples were collected. The pregnant rat's blood was collected from retro
orbital plexus. Then serum was separated and used for determination of serum
progesterone, estrogen, follicle stimulating hormone (FSH), Luteinizing hormone
(LH), serotonin and βendorphin levels. Tissue samples were taken from normal
group by opening of the abdominal cavity. Ovaries, ovarian ducts and uterus were
excised for histological examination. The results revealed significant increase in
progesterone, estrogen, LH, FSH and serotonin, and significant reduction in β
endorphin levels in acute non pregnant and pregnant groups. The chronic pregnant
and non pregnant groups showed, significant reduction in progesterone, estrogen and
LH and significant increase in FSH, serotonin and βendorphin levels.. βendorphin of
neonates showed significant reduction in neonates of rats exposed to chronic ethanol
injection and significant increase in neonates of rats exposed to chronic pain.
Histological examination showed reduction of uterine vascularity, leucocytes
infiltration, in rats exposed to acute stress of pain and ethanol injection. The chronic
groups showed dilated uterine lumen, increased uterine vascularity, leucocytes
infiltration and increased viable corpora lutea. It is concluded thatthe application of
stress of pain or injection of ethanol to female albino rats caused disturbance of
reproductive function. Also, ethanol injection to pregnant rats caused suppression in
βendorphin release in their offspring,, which may be due to apoptotic death of
neurons secreting βendorphin.