Effects of L-dopa on plasma levels of parathyroid hormone in calves.
After oral administration of l-dihydroxyphenylalanine (L-dopa) to calves, plasma concentrations of L-dopa, dopamine, norepinephrine and parathyroid hormone increased whereas prolactin and calcium decreased while epinephrine remained unchanged. The decrease of prolactin presumably occurred as a consequence of the conversion of L-dopa to dopamine (in the hypothalamus), whereas the increase in parathyroid hormone was caused by hypocalcemia, by elevated dopamine and possibly by norepinephrine.
D000284:Administration, Oral; D000818:Animals; D002118:Calcium / Q000097:blood; D002417:Cattle; D004298:Dopamine / Q000097:blood; D007980:Levodopa / Q000008:administration & dosage / Q000494:pharmacology*; D009638:Norepinephrine / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood*
D010281:Parathyroid Hormone; D007980:Levodopa; D002118:Calcium; D004298:Dopamine; D009638:Norepinephrine