Responses of parathyroid gland, C cells, and plasma calcium and inorganic phosphate levels in rat to sub-lethal heroin administration.

In order to record the effects of heroin on plasma calcium (Ca) and inorganic phosphate (Pi) levels as well as parathyroid gland and C cells, two sub-lethal doses (0.50 LD50 and 0.75 LD50) of the drug were administered intramuscularly in Rattus norvegicus for 30 days. Plasma Ca level of control rats ranged between 9.53 +/- 0.32 - 9.88 +/- 0.22 mg 100 ml(-1) while plasma Pi concentration fluctuated between 4.55 +/- 0.18 - 4.71 +/- 0.24 mg 100 ml(-1). Sub-lethal heroin administration induced progressive increase in plasma Ca level during the first seven days (p < 0.001), thereafter the level declined on day 15 and 30. However plasma Pi level of the heroin-treated rats registered increase with the peak value (p < 0.001) on day 30. The treatment elicited degenerative changes in parathyroid gland as evident by cytoplamic vacuolization, presence of more pycnotic nuclei and occurrence of patchy areas among the chief cells. Degenerative changes were also noticed in cristae of mitochondria, Golgi complex and endoplasmic reticulum. There was decrease in chromatin material in the nucleus and loss of hormone granules in the cytoplasm. Oxyphil cells of the heroin-treated rat depicted dilation of endoplasmic reticulum and damaged cristae. Sub-lethal heroin administration in the rat for 30 days induced dilation in endoplasmic reticulum and loss of secretory granules in C cells.