Abstract
Physiological effects of pyridoxal 5'-phosphate (PLP) on enzymatic reactions of cross-linking formation in collagen and elastin were studied. In the previous report of authors, it was observed that PLP combined with β-aminopropionitrile (BAPN) and considerably inhibited the BAPN induced depression of activities of vitamin B6 dependent enzymes in vitro. In this study, we performed an animal experiment using SD rats fed the lathyrogen (BAPN) and the effects of PLP on these animals were examined.
Thirty male SD rats were separated the following five groups: Group 1, three rats fed just a standard diet as control. Group 2, six rats receiving 250mg/kg/day of pyridoxine hydrochloride (PIN). Group 3, seven rats receiving 300mg/kg/day of BAPN. Group 4, seven rats receiving the same dose of BAPN as rats of group 3 and 125mg/kg/day of PIN. Group 5, seven rats receiving the same dose of BAPN as rats of group 3 and 250mg/kg/day of PIN. Authors observed the occurrence of death to be due to lethargic dissection of aorta for 189 days.
During the observation period, six rats of group 3 and six rats of group 4 died evidently on account of toxic effects of BAPN. But there were three survivors in group 5. It was generally observed that mean value of days required to occur lethargic dissection of aorta in group 5 was longer than those of groups 3 and 4.
From these results, it was concluded that the existence of sufficient dose of vitamin B6 may be necessary for mainteining the activity of lysyl oxidase which is the key enzyme for cross-linking formation of collagen and elastin, and lethargic dissections of aorta in rats caused with BAPN were inhibited by the administration of vitamin B6.
