Aldehyde fixation differentially affects distribution of diaphorase activity but not of nitric oxide synthase immunoreactivity in rat brain Buwalda, Bauke; Nyakas, C.; Gast, J.; Luiten, P.G.M. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. ABSTRACT: The effect of aldehyde fixation on NADPH-and NADH-dependent diaphorase (d) histochemistry and nitric oxide synthase (NOS) immunocytochemislry in the brain was investigated by comparing the distribution of these enzymes in in situ nitrocellulose blots of unfixed brain sections with that in aidehyde-fixed brain sections. Substitution of NADPH by NADH yielded no gross differences in cellular distbribution in the native blot, whereas in fixed sections NADH produced nonspecific staining of the entire section. In the in situ blot NADPHd histoohemislry therafore visualized general nitroblue tatrazolium reductass (NBTr) activity, which was particularly strong in hippocampal pyramidal neurons and cerabellar Purkinje cells. Aldehyde fixation abolished the anatomical pattern of general NBTr activity and changed the hiatochemical distribution in that of the NADPHd activity associated with the distribution of NOS-I immunoreacfivity (ir). Fixation intensified NADPHd histochemical staining in specific neurone, resulting in outstanding, Golgilike staining of these neurons in several brain regions, whereas the general NBTr activity in pyramidal and Purkinje cells disappeared, in contrast to the histochemical diaphorase dislribution, the distribution of NOS-I ir on blots and in aldehyde-fixed brain sections was similar. No NOS was observed in hippocampal pyramidal and carebellar Purkinje neurons. In regions like cerebral and cerebellsr cortex and striatum the applied anti NOS-I serum had a higher affinity for the native protein. It is concluded that aldehydes, rather than to progressively suppress NOS-unrelated enzymes, differentially elicit NADPHd activity in some groups of neurons while leaving NOS-ir unaffected.

Primary hyperparathyroidism (PHP) is rare during pregnancy and has been claimed to be associated with significant increase of neonatal morbidity and mortality. Whether the well recognized changes in calcium (Ca) and phosphate (Pi) homeostasis occurring in pregnancy might influence the biochemical expression of PHP is unclear. We evaluated biochemical parameters of calcium and phosphate metabolism in two cases of PHP in pregnancy diagnosed in the third trimester (patient 1) and in the second trimester (patient 2). Both patients displayed increase in protein-adjusted plasma Ca, bone resorption evaluated by the fasting urinary Ca-to-creatinine ratio, renal tubular reabsorption of Ca, urinary cAMP excretion and decrease in renal tubular reabsorption of Pi. These alterations were identical to those found in 12 non-pregnant women with PHP. The biochemical expression of PHP did not change after delivery in patient 1. This patient underwent the excision of a 1 g parathyroid adenoma on the 13th day after delivery, which led to normalization of all biochemical parameters. The lowest plasma Ca of the newborn of patient 1 was 2.02 mM 72 hours after birth. Thus, the results indicate that these two pregnant women with PHP displayed biochemical alterations of calcium and phosphate metabolism similar to those observed in non-pregnant women with primary hyperparathyroidism.