Immunocytochemical localization of PTHrP in human and rat salivary glands.

Parathyroid hormone-related protein (PTHrP) was isolated from tumours and is thought to represent the main factor responsible for humoral hypercalcaemia, which accompanies neoplastic diseases. At present, the protein is known to reside in multiple tissues and organs of both humans and animals. Our study was aimed at demonstrating the presence of PTHrP in normal salivary glands (parotid and submandibular) of rats and humans. Application of immunocytochemical techniques permitted to document the presence of PTHrP in the human and in the rat salivary glands. In all cases, an intense reaction was observed in intra- and interlobular ducts. In rat salivary glands, PTHrP was also present in cells of mucous acini. In our opinion, the presence of PTHrP in the ducts indicates participation of the protein in electrolyte transport across the epithelial cells. The positive reaction noted in mucous acini of rat salivary glands may indicate accessory role of PTHrP in the secretory processes in the glands.

Application of computed tomography in studies on development of human paranasal sinuses in the early postnatal period.

Seven skulls of newborns and of infants aged 3 weeks to 12 months were studied using computed tomography. Size of the maxillary sinuses was measured. Between 3rd and 12th week of life the ethmoidal sinus formed small spaces in ethmoidal labyrinth. Maxillary sinus could be noted at the level of lower orbital margin. In newborns, it formed a shallow indentation in the lateral wall of the nasal cavity. The anteroposterior dimension of the sinus was greater than the two remaining dimensions. Beginning from the 3rd month of life, number of ethmoidal cells increased, maxillary sinuses enlarged and entered the body of the maxilla. Between 6th and 12th month, the mediolateral and the superoinferior dimensions of the sinuses increased. Small air spaces were also seen in the part of sphenoid bone, corresponding to sphenoidal sinuses.

Immunocytochemical localisation of PTHrP (parathormone-related peptide) in myoepithelial cells of human sweat and parotid glands.

PTHrP is a HHM-inducing peptide. It exhibits certain structural similarity to PTH and the two hormones may act through the same receptors. PTHrP is known to be produced in various tissues as well as during development. In this study we decided to immunocytochemically demonstrate PTHrP in normal skin and squamous cell carcinomas as well as in parotid glands (normal, inflamed and neoplastic). In the skin, PTHrP expression was demonstrated in epidermis and in smooth muscle cell layer of blood vessels. In squamous cell carcinomas, the expression was noted in foci of keratinization. In parotid glands, the peptide was localised in excretory ducts and in blood vessels, while inflammation of the gland and its tumours resulted most frequently in the less intense immunoreaction. The results are consistent with those of other authors. The novel observations include demonstration of PTHrP expression in myoepithelial cells of sweat glands and in parotid glands, where it may be involved in the control of their contractile activity.

Histological and quantitative studies of the muscle spindles in human fetal infrahyoid muscles.

Muscle spindles were investigated in 19 human fetuses, aged 11 to 17 weeks. First spindles were observed in 11th week. The number of muscle spindles increases with advancement of the development being highest in the omohyoid muscle.

Number and localization of the muscle spindles in the human fetal sternocleidomastoid muscle.

The muscle spindles were counted in 16 sternocleidomastoid muscles of human fetuses aged 12-18 weeks. The greatest number of muscle spindles were noted in the middle of the sternocleidomastoid muscle.