Characterization, expression, and functional activity of pituitary adenylate cyclase-activating polypeptide and its receptors in human granulosa-luteal cells.
BACKGROUND
Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal polypeptide (VIP) are found in the ovary of mammalian species, although nothing is known about the possible role of PACAP and VIP in the human ovary.


OBJECTIVE
We investigated the expression of PACAP and PACAP/VIP receptors in human granulosa-luteal (GL) cells obtained from consenting in vitro fertilization patients attending a private fertility clinic and assessed a possible antiapoptotic effect of these molecules.


METHODS
We measured the expression of PACAP and PACAP/VIP receptor mRNAs in GL cells in response to FSH or LH, as well as the effects of PACAP and VIP on apoptosis. We also evaluated the levels of procaspase-3 in GL cells cultured in the absence of serum.


RESULTS
After 7 d in culture, GL cells displayed increased responsiveness to FSH and LH (100 ng/ml). FSH and LH promoted PACAP expression, LH doing so in a time-dependent fashion. VIP receptor (VPAC1-R and VPAC2-R) mRNAs were also induced by gonadotropin stimulation. Although PACAP receptor (PAC1-R) mRNA was barely detectable, Western blot analysis revealed its presence. The apoptotic effect of serum withdrawal from the culture environment was reverted by both PACAP and VIP. Both peptides showed the ability to reverse a decrease in procaspase-3 levels induced by culture in the absence of serum.


CONCLUSIONS
PACAP and VIP appear to play a role in maintenance of follicle viability as a consequence of the antiapoptotic effect. Further studies are warranted to evaluate the respective roles of PACAP and VIP in ovarian physiology and to identify their mechanism of action.
Morelli
Maria Beatrice
MB
Department of Histology and Medical Embryology, "La Sapienza" University of Rome, Via A. Scarpa 14, 00161 Rome, Italy.
Barberi
Marzia
M
Gambardella
Alessia
A
Borini
Andrea
A
Cecconi
Sandra
S
Coticchio
Giovanni
G
Canipari
Rita
R
D017209:Apoptosis / Q000187:drug effects; D051017:Apoptosis Regulatory Proteins / Q000502:physiology; D015153:Blotting, Western; D053148:Caspase 3 / Q000096:biosynthesis / Q000235:genetics; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D005260:Female; D005298:Fertility; D005640:Follicle Stimulating Hormone / Q000097:blood; D015870:Gene Expression / Q000235:genetics / Q000502:physiology; D006107:Granulosa Cells / Q000378:metabolism*; D006801:Humans; D008184:Luteal Cells / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000097:blood; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology*; D011374:Progesterone / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014660:Vasoactive Intestinal Peptide / Q000235:genetics / Q000378:metabolism
D051017:Apoptosis Regulatory Proteins; D016895:Culture Media, Serum-Free; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D012333:RNA, Messenger; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D014660:Vasoactive Intestinal Peptide; D011374:Progesterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D053148:Caspase 3