Histological study on the effect of sildenafil citrate (Viagra) on cerebral hemisphere of adult and aged male Albino rats

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Zahraa taboo
Eman Ghanim Sheet
Waleed Kasim


Sildenafil, brain, vacuolation, morphological, tissue



Objectives: Sildenafil(Viagra) is a known as perfect medications for treatment in patients agony from impotence and pulmonary arterial raised blood pressure, it cause numerous effects on the nervous system by “nitrogen monoxide-cyclic guanosine monophosphate pathway”. The current paper is designed to examine the histostructural  variations that may happen in the brain of both adult and elderly male rats after long course duration of Sildenafil(Viagra) drug treatment.  Material and Methods: Forty white albino male  rats  were bought from the veterinary  animal house   of  Mosul University.  Twenty of them were  between the ages of 3-4 months  ( adult ) while the others were between the ages of 22-24 months ( senile ). Grouр I ( 10 adult rats ) and grouр II ( 10  old age rats ) were given  distilled water and  regarded as control grouрs . Grouр III ( 10 adult rats ) and grouр IV  ( 10  old age rats )   were treated with Viagra in a dosage  of ten mg. kg. day  orally for thirty days. Results: The histological  sections from the control adult  group showed  normal architecture of the  frontal lobe cerebral cortex   with distinct multipolar neurons , many glial cells and prominent blood vessel while the cerebral cortex of adult rats from treated group showed  gliosis  with satellitosis (glial cells around neurons)vasogenic and cytogenetic edema  with perineuronal vacuolation and vascular congestion., there was mild shrinkage of some neurons Conclusion: Long-lasting administration with sildenafil citrate (Viagra) triggered a noxious outcome on the brain tissues with morphological changes in cells in both adults and the elderly male rats alike, although its effect was greater in the elderly, but this is not attributed to the drug as much as it contributes to the aging process.


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