Pulmonary endocrine cells in hypertensive pulmonary vascular disease

A study was made of the number of pulmonary endocrine cells, immunoreactive for gastrin-releasing peptide (bombesin) or calcitonin, in the terminal bronchioles of 39 cases of pulmonary vascular disease. In 25 of these, the form of vascular disease was plexogenic pulmonary arteriopathy, primary in 12 and secondary in 13, while the remaining 14 subjects had a wide range of other varieties of hypertensive pulmonary vascular disease. We found that pulmonary endocrine cells, especially those containing bombesin, were increased in number in both the primary and secondary forms of plexogenic pulmonary arteriopathy but not in other varieties of pulmonary hypertension. The prominent bombesin-containing cells were found in cases with cellular plexiform lesions but occurred even more prominently at an earlier stage when vascular smooth muscle cells were migrating from the inner media into the intima.

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Focal chronic thyroiditis and chronic carotid glomitis

The incidence of focal chronic thyroiditis and chronic carotid glomitis was studied by histological examination in 50 subjects over the age of 50 years coming to necropsy. The two conditions appear to be distinct, affecting different age groups. Focal chronic thyroiditis occurred as early as the sixth decade and was found on its own in 34 per cent of subjects. Chronic carotid glomitis was characteristic of the eighth and ninth decades and occurred on its own in 14 per cent of subjects. In a further 12 per cent, thyroiditis and glomitis co-existed. Chronic carotid glomitis has the same histological features as auto-immune thyroiditis, the infiltrate being composed of aggregates of lymphocytes and plasma cells, raising the possibility that it, too, has a basis in auto-immunity. The antigenic stimulus for the auto-immunity in the carotid bodies may be senescent nerve fibrils.

Carotid body disease and the physician--chronic carotid glomitis

There are three types of histological change in the carotid bodies which appear to have physiological and clinical associations. A prominence of the dark variant of chief cells with their contents of met-enkephalin and other peptides appears to be associated with acute exposure to hypoxia. Proliferation of sustentacular cells around the clusters of chief cells appears to be related to ageing and also to systemic hypertension. Recently we have described a new condition of chronic carotid glomitis which is characterized by follicles of lymphocytes and may have a basis in auto-immunity. In the present review we report for the first time plasma cell activity in the carotid bodies of an elderly man, especially around nerve fibrils and unmyelinated axons ensheathed in sustentacular cells. Such appearances are consistent with the view that ageing nerve fibrils may be the antigenic stimulus for the development of chronic carotid glomitis.

Chronic carotid glomitis

Both carotid bodies were obtained at necropsy from each of 75 subjects, 38 male and 37 female, ranging in age from 14 to 90 years. In each case the histological features were classified as one of four age-related patterns. The presence and distribution of lymphocytes were noted. They presented either as a diffuse scattering throughout the stroma or as large focal aggregates. In subjects over the age of 50 years the diffuse infiltrates occurred in 56% of cases and were virtually all T-cells. In the same age group the aggregates of lymphocytes were found in 21% of cases. These findings indicate that there is a disease of human carotid bodies characterized by focal aggregates of lymphocytes that begins in middle age and becomes increasingly common with advancing years, affecting 29% of subjects aged 70 years or over. It is not related to any co-existing disease but seems to be a response to the degenerative changes in the glomic tissues that occur with age. By analogy with comparable changes in the thyroid and salivary glands, the disease may have a basis in auto-immunity.

Pulmonary endocrine cells in pulmonary arterial disease

Pulmonary endocrine cells containing bombesin or calcitonin have been identified in human lungs by the peroxidase-antiperoxidase method. The numbers of such cells were greatly increased in patients with plexogenic pulmonary arteriopathy whether that condition was associated with primary pulmonary hypertension or with pulmonary hypertension from intracardiac shunts. The numbers of endocrine cells tended to be increased, but to a lesser extent in patients with pulmonary hypertension and medial hypertrophy of the muscular pulmonary arteries in the absence of plexogenic arteriopathy. Increased numbers of endocrine cells comprised both greater numbers of solitary cells and a pronounced clustering, often of a disorganized nature.

Pulmonary blood vessels and endocrine cells in subacute infantile mountain sickness

A male infant of 16 months, of the Han race, died from subacute infantile mountain sickness in Lhasa (3600 m). At necropsy there was right ventricular hypertrophy secondary to muscularization of the pulmonary arteries and arterioles thought to have been induced by hypobaric hypoxia. In addition, there was intimal proliferation of myofibroblasts in the pulmonary arterioles, venules and veins. There were increased numbers within the bronchioles of pulmonary endocrine cells, containing calcitonin and bombesin, which could be related to hypoxia or trophic effects on the pulmonary vasculature. The relation of delayed effects of hypoxia to primary pulmonary hypertension is considered in this study.

Anatomical variations in human carotid bodies

The variations in anatomical structure and position of both carotid bodies were noted in 100 consecutive subjects who came to necropsy. Considerable variations in form were found. Although most carotid bodies (83% on the right and 86% on the left) were of the classic ovoid type, an appreciable minority was bilobed (9% on the right and 7% on the left) or double (7% on the right and 6% on the left); 1% were leaf shaped. All these anatomical variants have to be distinguished from the pathologically enlarged carotid body that may have a smooth or finely nodular surface. Anatomical variants (such as the bilobed) may themselves enlarge as a consequence of carotid body hyperplasia.

Immunoreactivity to various peptides in the human carotid body

Human carotid bodies, removed at routine necropsies, have been subjected to radioimmunoassay for various peptides. Average levels of immunoreactivity, expressed in pm/g, were: met-enkephalin 612, leu-enkephalin 162, bombesin 73, neurotensin 67, VIP 9 and substance P 16. No alpha-hANP immunoreactivity could be detected.

Plexiform lesion in bronchopulmonary anastomosis

A cellular lesion developed in the bronchial component of a bronchopulmonary anastomosis in a girl of 6 years with primary pulmonary hypertension. Its histological features were consistent with those of a plexiform lesion.

Pulmonary endocrine cells in various species in the Himalaya

The numbers, morphology and distribution of pulmonary endocrine cells in goats, sheep and the yak and its interbreeds with cattle, dzos and stols, were studied after their demonstration by means of the peroxidase-antiperoxidase technique with a polyclonal antiserum raised in the rabbit to human neuron-specific enolase, a marker for neuroendocrine cells. The numbers, morphology and distribution were related to species and not to residence at high altitude. Pulmonary endocrine cells were common and mainly distributed as solitary cells in the epithelium of the bronchial tree in sheep. They were much less common and found mainly as clusters in the alveolar capillary walls in goats and in the yak and its interbreeds with cattle.

Subacute infantile mountain sickness

A description is given of a disease of infants occurring in Lhasa, Tibet at an altitude of 3600 m. Typically if affects infants who have been born at low altitude and subsequently brought to residue in Lhasa, and it is usually fatal within a few weeks or months. There is extreme medial hypertrophy of muscular pulmonary arteries and muscularization of pulmonary arterioles, together with dilatation of the pulmonary trunk and massive hypertrophy and dilatation of the right ventricle. The disease is distinct from acute or chronic mountain sickness and appears to be the human counterpart of 'brisket disease' in cattle.

[Pulmonary arterial hypertension and systemic lupus erythematosus. Apropos of 2 cases. Review of the literature]

Pulmonary arterial hypertension may develop in patients with systemic lupus erythematosus (SLE) in the absence of lung tissue lesion or embolism in the pulmonary circulation. Its mechanisms and prognosis are imperfectly known, although various suggestions have been made concerning the possible role of pulmonary arterial spasm, immune complex arteritis or arterial wall fibrosis. We report two cases of SLE in female patients who presented with clinical signs of pulmonary arterial hypertension. The fact that pulmonary arterial hypertension regressed completely in one patient and resulted in death in the other points to different pathogenic mechanisms. In the first patient the dramatic therapeutic effectiveness of a calcium inhibitor suggests that an arterial spasm was involved, whereas the anatomical lesions found in the second patient are in favour of a fibrotic inflammatory arteritis. This pathogenic heterogeneity of pulmonary arterial hypertension in SLE, which may correspond to different evolutive stages of the disease, is documented by a review of the literature with special attention to the frequency and to the clinical biochemical, haemodynamic and histological aspects of this complication of SLE.

Ultrastructure of early plexogenic pulmonary arteriopathy

A lung biopsy specimen from a young woman with the clinical features of primary pulmonary hypertension showed grade 2 plexogenic pulmonary arteriopathy. Electron microscopy revealed 'dark', electron-dense smooth muscle cells in the inner part of the media of muscular pulmonary arteries. Many of these transformed myocytes had migrated into the lumens of pulmonary arteries and arterioles which they occluded. This migration of smooth muscle cells was associated with a substantial increase in the number of pulmonary endocrine cells in the bronchioles containing bombesin and calcitonin.

A pathophysiological study of 10 cases of hypoxic cor pulmonale

A pathophysiological study of the pulmonary vasculature in 10 patients with hypoxic cor pulmonale and severe airways obstruction (five treated and five untreated with long-term oxygen) is presented. The media of muscular pulmonary arteries was normal or atrophic but, in the intima, there was active deposition of longitudinal muscle, fibrosis and elastosis. In the arterioles a medical coat of circular smooth muscle bounded by a new internal elastic lamina had developed, while there was deposition of longitudinal muscle and fibrosis in the intima. In five cases the lumen was subdivided into parallel tubes, found by serial section to lead into alveolar capillaries. These features are distinctive of hypoxaemia and obstructive airways disease. Changes continued until death. The conspicuous longitudinal muscle may be attributable to stretching of vessels round distorted terminal airways; further exploration into mechanisms is required. The hypothesis that vascular changes follow hypoxic vasoconstriction is no longer tenable. No correlations were found between quantitative pathological findings and arterial blood gas tensions, pulmonary artery pressure or haematocrit. There were no differences between patients treated or not treated with oxygen which might suggest that it arrests pathological changes. Thus, once a patient is given oxygen, survival probably depends as much on progressive mechanical changes in the lung as on continuing hypoxaemia.

Relation between histological age-changes in the carotid body and atherosclerosis in the carotid arteries

Histological changes in the human carotid body associated with increasing age are accompanied by occlusive atherosclerotic lesions in the arteries of the carotid bifurcation, and are probably ischaemic in origin. The carotid sinus, however, is unusually susceptible to the development of atheroma and its occlusion appears to have little influence in compromising blood flow through the glomic arteries.

Multicentre clinical trial of low volume fresh frozen plasma therapy in acute pancreatitis

Fresh frozen plasma (FFP) has been proposed as a specific therapy for acute pancreatitis. Reduced mortality encountered in an uncontrolled clinical study and a controlled experimental study may be attributable to replenishment by FFP of the naturally occurring antiprotease system. To investigate this potential therapy further, 202 patients presenting with acute pancreatitis were randomized to receive FFP (2 units daily for 3 days) or a similar volume of colloid control as part of their intravenous fluid therapy. Clinical progress was monitored and the major serum antiproteases (alpha 1-antiprotease and alpha 2-macroglobulin) were measured on days 1, 3 and 7. There was no significant difference between the two groups in terms of clinical outcome. alpha 1-Antiprotease levels rose significantly from day 1 to day 3 in both groups (P less than 0.0001) and remained elevated at day 7. alpha 1-Antiprotease is an acute phase protein in man and raised serum levels would be anticipated. FFP appears to have no effect on the magnitude of this rise. Serum alpha 2-macroglobulin levels were reduced in both groups on day 1 and continued to fall significantly from day 1 to day 3 in the colloid control group (P less than 0.005) whilst remaining substantially unaltered in patients receiving FFP (P = 0.6527). alpha 2-Macroglobulin plays a central role in the elimination of proteases during acute pancreatitis and the ability of relatively low volumes of FFP to reduce the fall in serum alpha 2-macroglobulin levels seen during the early stages of this disease may have therapeutic implications.

The pathology of the early and late stages of primary pulmonary hypertension

During the course of a case of primary pulmonary hypertension occurring in a 24 year old man lung tissue became available at heart-lung transplantation in 1986 and from a lung biopsy carried out in 1981. In 1986 the sections showed classic plexogenic pulmonary arteriopathy. In 1981 they revealed migration of myofibroblasts into the intima and lumen of pulmonary arteries and arterioles, the identification of the cells being confirmed by electron microscopy. During the five years that the pulmonary vascular pathology progressed to the formation of plexiform lesions there was an increase in the number of bronchiolar endocrine cells that were immunoreactive to bombesin and calcitonin. This study demonstrates that the classic pathogenesis of primary plexogenic pulmonary arteriopathy originates years earlier as a migration of cells of muscular pedigree from the media into the intima of the pulmonary arteries and arterioles.

Female ejaculation: its relationship to disturbances of erotic function

It is hypothesised that function of the female prostate homologue in small girls may be associated with shame resulting in inhibition of erotic function and sexual disturbance. This inhibition may explain the great variation to be found in female sexual experience.