Objective To assess human unstimulated whole saliva components during pregnancy, to determine the relation, if any, between pregnancy and oral health, particularly total protein concentration, a-amylase activity, sialic acid content and calcium and phosphate concentrations were evaluated.Design Cross-sectional study. Participants Forty-five healthy primigravid women; 1 5 nonpregnant women acted as controls. Results 1. A higher total protein content at 10 and 21 weeks of gestation with respect to the controls and to pregnant women at 40 weeks; 2. a higher a-amylase activity at 10 and 21 weeks of gestation compared with the controls and to pregnant women at 40 weeks; 3. an increased sialic acid content at 21 and 40 weeks; 4. decreased calcium and phosphorus concentrations at 21 and 40 weeks of gestation.Conclusions Pregnancy modifies saliva composition. This could play a pivotal role in the incidence of pregnancy-induced dental caries. INTRODUCTIONFemale steroid sex hormones influence oral health through different mechanisms. Gingival tissue is affected by hormonal changes during puberty and pregnancy, as shown by more pronounced subclinical signs of gingivial inflammation during the ovulatory phase of the menstrual cycle and by the worsening of pre-existing gingivitis during human pregnancy. Pregnancy induces an increased response of the gingival tissues to local factors, such as plaque and tartar, through disturbance of tissue metabolism4.Besides the direct effect on tissue metabolism, pregnancy and the menstrual cycle alter the composition of human saliva, as a response to the changed steroid hormone levels. Many human studies have indicated that hormones influence the composition of female saliva, particularly at the time of ovulation. Correlation has been found between the ovulatory status of women and the phosphate level5. A cyclic variation has been also observed in sialic acid, glucose and some salivary electrolytesG8. Saliva plays a critical role in the maintenance of oral health, as it contains many innate and acquired factors with a protective role on oral tissue^^.^^. rate have been reported, and changes in salivary electrolyte levels and IgA concentration have been A decrease in salivary HC03 during pregnancy has been related to the effect of progesterone in lowering plasma bicarbonate con~entration'~.'~. D'Alessandro et al. l6 have suggested a relation between the protein changes in parotid saliva and the hormonal modifications during pregnancy. Secretory proteins are produced by many salivary cell types and salivary total protein content could reflect general exocrine capacity". Many salivary proteins have enzymatic functions, such as a-amylase, which represents the major component of the parotid secretion and is also present in the submandibular fluid, representing about 50% of total proteins.Laine et al. I4 did not find significant changes in salivary amylase, lysozyme or peroxidase activities during pregnancy. Furthermore, the whole saliva levels of thiocyanate, hypothiocyanite, lactoferrin, to...

We studied the reflex arginine vasopressin (AVP) response to hypotensive, isosmotic fluid subtraction (by isolated UF) in 14 uraemic patients on renal dialysis treatment: five with normal autonomic function and nine with autonomic involvement of various degrees. Fluid subtraction caused a comparable mean arterial pressure (MAP) decrease in the two groups. The reduction in right atrial pressure was inversely related with the severity of autonomic neuropathy (rs = -0.72, P = 0.004), being distinctly attenuated in the second group (P = 0.006). Plasma arginine vasopressin increased similarly in patients with normal autonomic function and in those with autonomic involvement. The response of patients with haemodialysis hypotension was similar to that of other patients. Reflex control of arginine vasopressin is preserved even in the presence of afferent/central neuropathy or more advanced, widespread autonomic damage in uraemic man. The data suggest that it is unlikely that altered release of arginine vasopressin is involved in the pathogenesis of haemodialysis hypotension.

Plasma membrane lipid dynamics and cellular morphology were evaluated in endothelial cells obtained from umbilical cords of five women affected by insulin-dependent diabetes mellitus (IDDM) and six healthy pregnant women of similar age and gestational age. Endothelial cells were prepared by an adaptation of the method of Jaffe et al. Membrane fluidity was studied by means of the steady-state fluorescence anisotropy (r) of 1-(4-trimethylaminophenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), a fluorescent probe specifically anchoring at the membrane surface. Fluid phase endocytosis was evaluated by the measurement of the changes in fluorescence intensity of TMA-DPH at various times, owing to the internalization of the fluorescent marker in endocytic vesicles. The morphological and morphometric studies were performed by means of transmission electron microscopy (TEM). Endothelial cells obtained from IDDM women showed: (a) increased fluidity of the superficial region of the plasma membrane; (b) a more active fluid phase endocytosis compared with cells from healthy women; (c) increase in mitochondrial area, Weibel-Palade bodies and rough reticulum with wide cisternae. No statistically significant correlation was found between metabolic control and membrane fluidity and endocytosis. All the observed modifications suggest the presence of endothelial cell activation with membrane reshaping during IDDM. These alterations might play a central role in the pathophysiology of atherosclerosis and microangiopathy associated with diabetes mellitus.

No abstract