THE EFFECT OF TEMPERATURE ON THE TURNOVER OF TASTE BUD CELLS IN CATFISH

Renewal of taste bud cells on the barbels of channel catfish was studied. Groups of catfish, held in and acclimitized to 14 degrees C, 18 degrees C, 22 degrees C and 30 degrees C dechlorinated tap water were injected with [3H]thymidine (3.0 muCi/g body weight intraperitoneally). Barbels were sampled at various times after injection and prepared for light microscope autoradiography. Results show that epithelial cells surrounding the taste buds divide and some of their daughter cells migrate into the taste buds. The time at which 50% of the labelled cells have degenerated is taken as the average turnover time or average life span of the taste bud cells. The average life span as well as the time spent inside the taste buds is highly temperature-dependent. At 14 degrees C, 18 degrees C, 22 degrees C and 30 degrees C the average life span is on the order of 40, 30, 15 and 12 days respectively. Further studies indicate that both light and dark staining cells of the taste bud were labelled.