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Cysteine-rich secretory protein 1 (CRISP1) is a secretory glycoprotein produced by the rat epididymal epithelium in two forms, referred to as proteins D and E. CRISP1 has been implicated in sperm-egg fusion and has been shown to suppress capacitation in rat sperm. Several studies have suggested that CRISP1 associates transiently with the sperm surface, whereas others have shown that at least a portion of CRISP1 persists on the surface. In the present study, we demonstrate that protein D associates transiently with the sperm surface in a concentration-dependent manner, exhibiting saturable binding to both caput and cauda sperm in a concentration range that is consistent with its capacitation-inhibiting activity. In contrast, protein E persists on the sperm surface after all exogenous protein D has been dissociated. Comparison of caput and cauda sperm reveal that protein E becomes bound to the sperm in the cauda epididymidis. We show that protein E associates with caput sperm, which do not normally have it on their surfaces, in vitro in a time- and temperature-dependent manner. These studies demonstrate that most CRISP1 interacts with sperm transiently, possibly with a specific receptor on the sperm surface, consistent with its action in suppressing capacitation during epididymal storage of sperm. These studies also confirm a tightly bound population of protein E that could act in the female tract.

The aim of this study was to determine gross and neuroanatomic features of a novel periurethral neuromuscular electrostimulator. Periurethral leads were placed in eight female cadavers. In two cases, leads were imaged after placement to enhance anatomic understanding. Pelvic viscera were removed en bloc for analysis of lead placement in the six remaining cadavers. Excised tissue was sectioned and immunostained to identify general, afferent, sympathetic, and nitric oxide synthase efferent nerve fibers. The electrodes were found within/lateral (n = 4), within/posterolateral (n = 9), and anterolateral (n = 1) to the external urethral sphincter (distance 0.25 +/- 0.5, 2.9 +/- 3.3, and 1.0 +/- 0.0 mm, respectively). The electrode to the urethra and vagina distance averaged 7.6 +/- 3.4 and 8.8 +/- 4.3 mm, respectively. Variable density staining for all nerve types was found around the electrode. A periurethral electrode interfaces the external urethral sphincter, and the adjacent distribution of nerve fibers supports proposed neuromuscular therapeutic mechanisms.

Cysteine-rich secretory protein-1 (CRISP-1) is a glycoprotein secreted by the epididymal epithelium. It is a member of a large family of proteins characterized by two conserved domains and a set of 16 conserved cysteine residues. In mammals, CRISP-1 inhibits sperm-egg fusion and can suppress sperm capacitation. The molecular mechanism of action of the mammalian CRISP proteins remains unknown, but certain non-mammalian CRISP proteins can block ion channels. In the rat, CRISP-1 comprises two forms referred to as Proteins D and E. Recent work in our laboratory demonstrates that the D form of CRISP-1 associates transiently with the sperm surface, whereas the E form binds tightly. When the spermatozoa are washed, the E form of CRISP-1 persists on the sperm surface after all D form has dissociated. Cross-linking studies demonstrate different protein-protein interaction patterns for D and E, although no binding partners for either protein have yet been identified. Mass spectrometric analyses revealed a potential post-translational modification on the E form that is not present on the D form. This is the only discernable difference between Proteins D and E, and presumably is responsible for the difference in behavior of these two forms of rat CRISP-1. These studies demonstrate that the more abundant D form interacts with spermatozoa transiently, possibly with a specific receptor on the sperm surface, consistent with a capacitation-suppressing function during sperm transit and storage in the epididymis, and also confirm a tightly bound population of the E form that could act in the female reproductive tract.

Objectives Idiopathic calcium oxalate (CaOx) stones are believed to develop attached to papillary subepithelial deposits called Randall's plaques. Calcium phosphate (CaP) stones, conversely, are thought to arise within the inner medullary collecting ducts, enlarging and damaging surround tubular structures as they expand. If this is true, we theorize that differences will be seen within the organic portion (matrix) of CaOx stones compared with CaP stones using a mass spectroscopy (MS) approach. Methods From a cohort of 47 powdered stones, 25 calculi (13 CaOx, 12 CaP) were confirmed to contain a dominant mineral content of >80% by powder x-ray diffraction. Matrix proteins were then extracted, purified, and digested. Peptide tandem MS data were acquired, and spectra were searched against a large human protein database to identify protein matches. Results No significant differences were seen between pattern profiles of CaOx and CaP stones. However, variations in protein expression patterns were seen within individual CaOx (monohydrate and dihydrate) and CaP (apatite and brushite) mineral subtypes, suggesting a relationship between crystal-surface binding properties and matrix composition. Both groups contain a large number of inflammatory proteins and a catalog of common proteins is included. Conclusions Calcium kidney stone matrix contains hundreds of proteins and is predominated by proteins associated with inflammatory response. Many of the same proteins were identified in both CaOx and CaP stones, suggesting inflammation as a unifying origin or a common secondary role in calcium stone pathogenesis.