Responses of serum adrenocorticotropic hormone (ACTH) and cortisol levels as well as adrenal cortex of Mus norvegicus to sublethal heroin administration

Sublethal (13.5 mg/kg/day; 0.5 LD₅₀ for 96 hours) heroin administration in Mus norvegicus induced significant decline in serum ACTH and cortisol levels at 24 hours of treatment which progressed till day 30. Though cells of all the three zones of adrenal cortex were affected by heroin treatment, zona fasciculata cells depicted maximum degenerative changes. The cells of zona fasciculata of control rat were cuboidal or polyhedral in shape, round nucleus with prominent nucleolus and well-distributed chromatin material, large number of mitochondria, lipid droplets, rough endoplasmic reticulum (RER), Golgi complex and lysosomes. Sublethal heroin administration for 30 days induced marked deposition of chromatin material in the inner cell membrane, mitochondria with damaged cristae, less secretory granules, scattered free riobosomes pycnotic nucleus and cytoplasm filled with minute vacuoles. Cytoplasm of many cells was devoid of cell organelles and remnants of endoplasmic reticulum, mitochondria and granules were also encountered on day 30 of the treatment.