Figure 5. Longevity is inversely associated with testicular apoptosis. Quantification of apoptotic cells in testes of GH-Tg short-lived mice, GHRH-KO and Ames dwarf long-lived mice and their normal littermates was determined by TUNEL assay using a light microscope with a magnification of 400x and a gridded eyepiece. Results are expressed as TUNEL-positive cells/mm2 and TUNEL-positive cells/tubule. Bar plot graphs represent the mean + SEM; n = 5-7. * p < 0.05, t-Student test.