Faculty Bibliography

Degradation of melanotropin inhibiting factor (MIF) was measured by fluorometry, using pareptide as an internal standard, following the separation of the dansyl derivatives of MIF and its metabolites by HPLc. MIF was not split by carboxypeptidases A and B, prolidase, or pyroglutamate aminopeptidase. It was hydrolyzed by leucine aminopeptidase, aminopeptidase M, and carboxypeptidase Y. Rat brain hydrolyzed 159 nmol of MIF per mg of protein per h; the activity was linear with enzyme concentration. Hydrolysis start from the N-terminal end, as shown by the appearance of proline as the first metabolite of the MIF degradation, followed by leucine, glycinamide, leucylglycine, and glycine. Activity in the rat brain regions was in the order striatum, medulla oblongata > cortex, hippocampus, midbrain > hypothalamus, cerebellum, and pituitary. The enzyme was mostly in the supernatant, with significant amounts in the myelin and synaptosomal fractions. MIF aminopeptidase could be separated from carboxypeptidase by centrifugation at 30,000 x g for 20 min and precipitation with 45--75% (NH4)2SO4. It showed pH optima in the alkaline range (8.25 and 8.75) and was inhibited by EDTA, EGTA, SQ 14,225, puromycin, bacitracin, and bestatin

N,N-Dimethyl diethyl, dipropyl, dibutyl, and N-monoisopropylaminoaphthylenesulfonyl derivatives of melanotropin inhibiting factor (MIF) and its metabolites were prepared, and their chromatographic behavior was investigated with thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), using five solvent systems on polyamide layers and ten solvent systems on muBondapak C18 and muBondapak phenyl columns. A mixture of MIF and its metabolites derivatized with Dns chloride was adequately resolved by two-dimensional chromatography on polyamide layer with solvent systems, formic acid-water (3:97) and benzene-acetic acid (9:1). Bns-MIF and its metabolites were separated with muBondapak C18 column with the solvent system acetonitrile-0.01 M sodium sulphate buffer, pH 7 (50:50). They were separated into five groups: Gly and Bns acid; Pro-Leu, Leu-Gly and Leu; Pro; Gly-NH2; and MIF. The alkylaminonaphthylenesulfonyl derivates had strong fluorescence, which permitted their detection at the level of 10(-11) to 10(-9) mol. Dns-MIF and its derivatives had the lowest detectable amounts. HPLC with the aid of the Dns derivation is reliable and fast, and is the preferable method for study of neuropeptide breakdown

Choline acetyltransferase (CAT) and acetylcholinesterase (AChE) activities were measured in spinal cord homogenates from rabbits with aluminum-induced neurofibrillary degeneration and a group of saline-treated, age-matched controls. All aluminum-treated animals showed neurofibrillary changes in the spinal cord, but CAT and AChE activities were not significantly different from levels in control animals. These results are at variance with the greatly reduced activity of these enzymes observed in Alzheimer disease and senile dementia of the Alzheimer type

Regional distribution of choline acetyltransferase (CAT) and acetylcholinesterase (AChE) in seventeen regions of the rabbit CNS has been determined by means of the cation exchange radiometric method. A significant correlation has been found between the activities of AChE and CAT which allows computation of their potencies. A comparison between activities of the cholinergic enzymes in the human and rabbit brain has been discussed

Eight novel methylcarbamates, derivates of ferrocenylketoximes and aldoximes, and ferrocenyl-p-hydroxyphenylaldimine were prepared. They are the first carbamates in the field of ferrocene derivatives. Their anticholinesterase activity was tested and found to fall in the range of 10(-4) through 10(-6) M (I50). The correlation between the activity of the compounds and the kind of substituents grafted on the methylene carbon atom is discussed