The Effect of Alterations of pH on Ketogenesis in Isolated Rat Hepatocytes

Abstract

Medical Research Society 2 5~ 65 mmm up o m 25 HTDROXTPITANI~Q D ow CALCIUM ABSORPIION AND PLASMA 1,25 DIdEDXY-VITAMIN D IN CORTICOSTEROD -Ell m S Q . TAYLOR AND J. STORER FreHospital, 1Jewcaatle Upon b e , and lQtc Hineral Yetabolism Unit, General Infirmary,Leeds Corticosteroid treated subjects with spinal OsteopOrOEds have calcium malabsorption and low 1,25 dihydroryrritamin D (1,25(0HJ2D) levels, wherean those without osteoporosis are nolmal i n Science 62, 4 1 p . ) . Ye report here the effect on 1,25[OH),D levels and calcium absorption of oral 25 @droqvvitamin D 25 jag daily given t o 13 osteoporotics(B) and 11 non-osteoporotics (no-) on lomptenn prednisolone. me groups w e r e of similar age (62.8 + 2.65 (SE) vs 59.1 2 2.91 yrn respectively, diflerence H.S.), had been on preduisolone f o r similar periods of time ourrently receiving-similar doses (8.2 5 2.31 vs 7 . 5 9 0.95 ag/&aY, H.S.). 250HD3 treatment was given for 3-12 months (6.92 f 0.87 vs 6 . 0 2 0.73 &ha N.S.). h t i n g radiocalcimn absorption y88 a a s m before and on treatment. Initial and treated 25OHD levels were similar in each group (8, 89.3 f 10.3 aud 182.5 + 11.3 hmol/l p<O.001; n-, 96 f 10.3 and 177.3 5 14.5 nmol/l p < 0.005). Calcium absorption rose but only significantly eo i n the non-Bs (OP from 0 . 4 + 0.05 t o 0 . 5 1 + 0.05 fraction/hour, n.s.; noaFaP froln 0.54 +-o.08 t o 0.8 + 0.09 fr/hr, p < 0 . 0 2 ) . Pla& 1,25(OH)p l&ls rose in both groups, but only significantly so in the 6 s (8 frm 6 1 . 8 5 6 . 0 t o 95.1 + 4.82 pmol/l p < 0.001; nolr6 99.8 + 9.8 t o 1;?7.6 5 15 pmo1/4 M.S.). In the baselin; s t a t e 8 subjects had significantly lower 1,25(0H) D levels (p<QOq). The calcium absorption, tho& lower, y88 not signifioantly 80. had larer l,25(OH)2D levels (p< 0.05) and oaloiop absorption (p< 0 . 0 1 ) , than the n d s . Calcium absorption in both gropps before and on treatment seems levels. The 1,25(03 D levels in the 8 s rise on therapy and the inltial low level6 cm be nomalised, but the l,25(OH)2D levels remain lower in the B s for any given 25OHD level. The basic cause of the low l,25(OH)2D levels in 8 steroid-treated subjects replains unclear. R . Q . CFULLT, N . PEACOCK, B. E. C. NORDIN, both reEpects. (Crilly e t a l e , (1982)s C l i n i c a l (10.7 f 2 . 2 W 7 . 4 + 2.13 m, M A ) a d were -9and plasm 250RD a d l,25(OH)2DOn treatment, the 8 s still p q r i a t e t o the lr25(OH)2D