Nitric oxide may mediate nipple erection.

The nipple is a specialized structure that can become erect by cold, sexual arousal, breast-feeding, or other tactile stimulations, which can induce the milk ejection reflex and sexual arousal because of intense sensory innervation. The studies that have been conducted thus far to identify the mechanism of nipple erection (NE) are not sufficient. It has been stated that NE occurs via activation of the sympathetic nervous system and smooth muscle contraction. The purposes of this study were to investigate the existence of nitric oxide synthase (NOS) in the nipple-areola complex (NAC) to explain the NE mechanism. Considering that smooth muscle relaxation might be effective in NE, endothelial and neuronal NOS expression and localization were investigated via immunohistochemical methods on sagittal sections from 17 human NACs. The results of this study indicate that eNOS is expressed in the vascular endothelium, ductal epithelium, and smooth muscles, whereas nNOS is expressed in the neural fibers, smooth muscles, ductal epithelium, and vascular endothelium in the NAC. Sinusoidal spaces with endothelial layers similar to those found in penile cavernosal tissue are not found in the NAC. Various mediators are known to affect the function of the NAC smooth muscles; however, this study demonstrates that enzymes (eNOS and nNOS) that synthesize nitric oxide are expressed in the NAC.

Breast cancer diagnosis by lactate dehydrogenase isozymes in nipple discharge.

BACKGROUND: The diagnosis of breast cancer based on nipple discharge, often the only clinical manifestation of early breast cancer, is currently unsatisfactory. Because M subunits of lactate dehydrogenase (LDH) have been noted to increase in cancer tissue, the author assessed the value of using LDH isozyme patterns in nipple discharge for the diagnosis of breast cancer. METHODS: LDH isozyme levels in (1) nipple discharge of patients diagnosed as having breast cancer, intraductal papilloma, mastopathy, drug-induced nipple discharge, mastitis, or benign nipple discharge; (2) control samples of normal nipple discharge (milk) 6 days, 1-5 months, and 6 months to 2 years postpartum; (3) the serum of patients presenting with nipple discharge; and (4) normal and cancerous breast tissue extracts were measured using a Ciba-Corning LDH isozyme system (Ciba Corning Diagnostic Corp., Tokyo, Japan). RESULTS: LDH isozyme levels in the nipple discharge of patients with benign breast diseases displayed various patterns. Levels in the nipple discharge of patients with breast cancer, including noninvasive carcinoma, tended to increase in ascending order from LDH1 to LDH5. This pattern was similar to that in breast cancer tissue and was unrelated to the pattern in serum. CONCLUSION: LDH isozyme assay of nipple discharge may be a useful technique for providing a supporting diagnosis of breast cancer.

Hereditary acrolabial telangiectasia. A report of familial blue lips, nails, and nipples.

We describe a mother and two daughters who had the following clinical manifestations: bluish discoloration of the vermillion ridge of the lips, nipple areolae, and nail beds; discrete telangiectasia of the chest, elbows, and dorsa of the hands; varicosities of the lower part of the legs; and (in the two daughters) migraine headaches. Routine histologic examination of tissue from the lips and elbows disclosed extensive, dilated, horizontal subpapillary telangiectases. Enzyme histochemical stains demonstrated activity of adenosine triphosphatase and leucine aminopeptidase around these dilated vessels. Alkaline phosphatase activity was strikingly absent from the dilated subpapillary vessels. By electron microscopy, these vessels were demonstrated to be postcapillary venules. We propose an autosomal dominant mode of inheritance.