Ronald E. Chance

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C-peptide, a cleavage product from the processing of proinsulin to insulin, has been considered to possess little if any biological activity other than its participation in insulin synthesis. Injection of human C-peptide prevented or attenuated vascular and neural (electrophysiological) dysfunction and impaired Na+- and K+-dependent adenosine triphosphate(More)
Inversion of the natural sequence of the B chain of human insulin (HI) from ProB28LysB29 to LysB28ProB29 generates an insulin analogue with reduced tendency to self-associate. Since this substitution increases the homology of insulin to insulin-like growth factor-I (IGF-I), we have examined the affinity of a series of insulin analogues with the general(More)
The importance of ProB28 and LysB29 on the self-association of insulin was established by systematically truncating the C terminus of the B chain. The relationship between structure and association was further explored by making numerous amino acid replacements at B28 and B29. Association was studied by circular dichroism, size-exclusion chromatography and(More)
Traditionally, neuropeptide Y (NPY) receptors have been divided into Y1 and Y2 subtypes based on peptide pharmacology and synaptic localization. Other receptor subtypes have been proposed based on preferences for NPY, peptide YY (PYY), or pancreatic polypeptide (PP). Recently, we discovered a novel human member of this receptor family exhibiting high(More)
Proinsulin in nearly homogeneous form has been isolated from a preparation of porcine insulin. A molecular weight close to 9100 was calculated from the amino acid composition and from sedimentation-equilibrium studies. Through the action of trypsin this single-chain protein is transformed to desalanine insulin by cleavage of a polypeptide chain connecting(More)
In 21 normal fasting subjects basal serum-pancreatic-polypeptide (H.P.P.), as measured by a specific radioimmunoassay, was 43 +/- 4 pmol/l (mean +/- S.E.M). This basal concentration was of the same magnitude as that of other gastrointestinal peptide hormones. In normal subjects the H.P.P. response to food was bisphasic. A rapid eightfold increase, reaching(More)
Three nonargentaffin rectal carcinoids have been investigated immunohistochemically. In one case most tumor cells reacted with antiglucagon sera as well as with antiglicentin, antibovine pancreatic polypeptide (BPP), and antihuman pancreatic polypeptide (HPP) sera; they were identified ultrastructurally as L cells. Another case showed glucagon-, glicentin-,(More)