Figure 4. Expression of p53 mRNA in the heat-treated monkey testis. (A) In situ hybridization analysis of p53 mRNA expression in testis of monkey before (Pre) and after heat stress (day [D]3, D8, D30, D84, D144). Dark blue color shows the positive signal. Con indicates negative control with sense probe on D8 sections. Bar 5 100 mm. (B) Reverse transcription polymerase chain reaction analysis of p53 mRNA expression in the heat-treated monkey testis. mRNA levels were determined by densitometry. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as the internal control. The relative intensity was the ratio of p53 mRNA to GAPDH. Data are presented as mean ± SEM (n = 3). ^* P < .05; ^** P < .01). M indicates 1 kb plus DNA marker (bp).