Journal of the Dow University of Health Sciences (May 2009)
A HISTOLOGIC STUDY OF CARBIMAZOLE-INDUCED HYPERPLASIA OF ADENOHYPOPHYSIS WITH PROTECTIVE ROLE OF THYROXINE IN MALE ALBINO RATS
Abstract
Objective ' To assess the frequency and degree of pituitary hyperplasia in albino rats made hypothyroidby Carbimazole, and the association of severity of pituitary enlargement, and the response to treatment withthroxine. To determine the microscopic changes occurring in Beta basophil cells (Thyroid stimulatinghormone & Adreno corticotrophin hormone producing cells) o f Anterior Pituitary gland by giving an antithyroiddrug, Carbimazole and Carbimazol plus Thyroxin on Anterior pituitary glands o f male albino ratswith increasing time period. Design' Experimental study Place: Anatomy Department, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre Karachi. Methods: Forty five healthy, young adult male albino rats were selected for the study. They were distributedinto 3 main groups of 15 rats each. Group A served as control while Group B received injection Carbimazole6 ^gm/G body weight subcutaneously daily. Group-C were treated with injection Carbimazole 6 ^gm/Gbody weight subcutaneously plus injection Thyroxin 5 ^gm intraperitoneally daily for their respective periodo f treatment. Each group was further subdivided into three sub-groups according to the period o f treatmentthey received i.e. 2, 4 & 6 weeks at the end o f which animals were sacrificed. The Pituitary glands weredissected out after processing and staining (Wilson-Ezrin method). The tissues were subjected to detailedmicrometric examination. Result' The results are based on changes in morphometric study o f number and diameter ofBeta Basophilcells in anterior Pituitary gland. Mean value o f number o f Basophils were increased significantly (P <0.001)in group B (Carbimazole treated) i.e 151.0± 3.38 than group A (control) i.e 82.2 ± 3.48. While in group C(Carbimazole plus Thyroxin treated) the number of cells were decreased i.e 117.6 ± 3.83 than group B butwere more than group A, Beta Basophil cell size (diameter) was also increased significantly (P <0.001) ingroup B i.e 17.64 ± 1.06 than group A 14.45 ± 3.28.In group C Beta Basophil cell size was16.16 ± 2.02, which was more than group Abut less than group C.The number and size o f Beta Basophils in group C was significant (P<0.05), when compared withcorresponding controls. Conclusion'. In conclusion these results strongly suggest that Carbimazole-induced hyperplasia andhypertrophy of Anterior pituitary gland may be prevented by simultaneous treatment with Thyroxin. Longstanding treatment with Carbimazole in Hyperthyroid patients as in Graves disease should accompany, smalldoses of Thyroxin as well, to avoid the enlargement of Anterior Pituitary gland during their treatment.
