Immunohistochemical localization of anterior pituitary cell types of vervet monkey (Chlorocebus aethiops) following sub-chronic cathinone exposure.
BACKGROUND
Khat (Catha edulis) contains cathinone, an active principal that is customarily used as a psychostimulant that wards off fatigue and to some extent used as an aphrodisiac.


OBJECTIVE
To investigate effects of escalating doses of cathinone on hormone expression by different anterior pituitary cell types using specific antibodies.


METHODS
Eleven vervet monkeys (6 males and 5 females) divided into tests (n=9) and controls (n=2) were used. Animals were allocated as group I (saline controls), group II (0.8 mg/kg), group III (3.2 mg/kg) and group IV (6.4 mg/kg) of cathinone. All treatments were via oral route at alternate days of each week. At the end of 4-month treatment phase, GnRH agonist (ZOLADEX) was administered to group II (low dose) and group IV (high dose) alongside cathinone for 2 additional weeks.


RESULTS
High cathinone dose at long-term exposure caused proliferation of gonadotrophs but decrease in lactotrophs and corticotrophs in anterior pituitary sections of animals while effect of low dose on these cells was insignificant. Subsequent GnRH agonist co-treatment with low and high cathinone doses enhanced gonadotroph proliferation but no change on decline of lactotrophs and corticotrophs.


CONCLUSIONS
We believe that there was a possible potentiation of cathinone on pituitary hormone synthesis thereby influencing reproductive function. Suppression of corticotrophic and lactotrophic functions suggest lowering of stress levels and modulation of reproductive function based on dose level and chronicity of exposure. The findings are consistent with the hypothesis that cathinone interferes with pituitary cell integrity and consequently target organs, but further studies are required to address the precise mechanism underlying this phenomenon.
Department of Veterinary Anatomy and Physiology, University of Nairobi, P.O. Box 30197, 00100 Nairobi, Kenya. Electronic address: kimungui2002@yahoo.com.
Albert
A
Nyongesa
Department of Veterinary Anatomy and Physiology, University of Nairobi, P.O. Box 30197, 00100 Nairobi, Kenya.
Jemimah
J
Oduma
Duluth Medical Research Institute, University of Minnesota, Duluth, MN 55812, USA.
Mustafa
M
al'Absi
Department of Neuroscience and Pharmacology, Meharry Medical College, Nashville, USA.
Sanika
S
Chirwa
D000470:Alkaloids / Q000008:administration & dosage* / Q000032:analysis*; D000818:Animals; D029754:Catha; D000697:Central Nervous System Stimulants / Q000008:administration & dosage / Q000032:analysis; D002522:Chlorocebus aethiops; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D010903:Pituitary Gland, Anterior / Q000737:chemistry* / Q000187:drug effects; D010936:Plant Extracts / Q000008:administration & dosage* / Q000032:analysis*
D000470:Alkaloids; D000697:Central Nervous System Stimulants; D010936:Plant Extracts; C023665:cathinone
HPA axis; Immunohistochemistry; Monkey; Pituitary