Peripheral plasma met-enkephalin levels in ovulatory and anovulatory human menstrual cycles.
OBJECTIVE
To test the hypothesis that met-enkephalin has a role in human ovulation and that plasma levels may differ between ovulatory and anovulatory ovarian cycles.


METHODS
This is a descriptive study comparing levels of plasma met-enkephalin, gonadotropins, and ovarian steroids in 12 ultrasonically confirmed ovulatory cycles and 12 anovulatory cycles.


METHODS
The study took place in the infertility clinic of a large teaching hospital receiving primary and tertiary referrals of both private and public sector patients.


METHODS
All patients (n = 16) had infertility greater than or equal to 3 years and normal findings on previous investigation including evidence of ovulation.


METHODS
Ovarian cycles were defined using transabdominal ultrasound scanning. Biochemical analyses were by radioimmunoassay.


METHODS
The differences between plasma met-enkephalin levels in the two groups of cycles were compared.


RESULTS
Met-enkephalin levels are significantly higher in ovulatory cycles with a significant peak in the 2 postovulatory days (Duncan's multiple range test; P less than 0.05).


CONCLUSIONS
Human ovulation is associated with cyclic elevation of plasma met-enkephalin. Further studies are required to elucidate causality.
Saad
E A
EA
Department of Obstetrics and Gynaecology, St. James's University Hospital, Leeds, United Kingdom.
Bromham
D R
DR
Bhabra
K
K
Ambrose
C L
CL
D000858:Anovulation / Q000097:blood*; D004744:Enkephalin, Methionine / Q000097:blood*; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007247:Infertility, Female / Q000097:blood*; D007986:Luteinizing Hormone / Q000097:blood; D008597:Menstrual Cycle / Q000502:physiology*; D010060:Ovulation / Q000502:physiology*; D011374:Progesterone / Q000097:blood
D011374:Progesterone; D004958:Estradiol; D004744:Enkephalin, Methionine; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone