Brendan John Gannon

Treatment of Postmastectomy Lymphedema with Low-Level Laser Therapy A Double Blind, Placebo-Controlled Trial

The current study describes the results of a double blind, placebo‐controlled, randomized, single crossover trial of the treatment of patients with postmastectomy lymphedema (PML) with low‐level laser therapy (LLLT).

Endothelial Distribution of the Membrane Water Channel Molecule Aquaporin-1: Implications for Tissue and Lymph Fluid Physiology?

BACKGROUND Aquaporin-1 (AQ-1) is a transmembrane water channel protein reportedly expressed in continuous capillary endothelium and intestinal lacteals. We investigated endothelial AQ-1 expression in rat intestine and mesentery, and also in lymph nodes. METHODS AND RESULTS Rat intestine, mesentery, and lymph nodes were immunolabeled for AQ-1, revealing membrane expression in endothelial cells of vascular continuous capillaries and venules, and of initial and conducting lymphatics. Blood vessel profiles were identified with RECA-1 and circulating FITC-albumin. In nodes, capillaries and high endothelium venules (HEVs) showed AQ-1 labeling, as did intranodal lymphatic sinusoidal endothelium and reticular cells. CONCLUSIONS The labeling pattern of vessels with RECA-1, AQ-1, circulated FITC albumin, plus elastin autofluorescence permitted identification of arteriolar, continuous, and fenestrated capillaries and lymphatic vessels in tissue sections. Strong AQ-1 expression in continuous microvascular and initial lymphatic endothelium suggests its possible involvement in tissue fluid exchange between plasma and interstitial fluid, and perhaps between interstitial fluid and initial lymph. Endothelial AQ-1 expression was strong in lymphatic sinusoidal endothelium and intense in HEVs. This described endothelial AQ-1 expression has potential implications for tissue fluid physiology. Lymph protein is known to concentrate in lymph nodes by fluid loss, so AQ-1 may facilitate lymph to plasma water flux. Starling forces may not drive this flux, and we discuss a possible osmotic mechanism; consequently we hypothesize a suite of ion pumps/channels/exchangers/cotransporters in nodal vascular (probably HEV) endothelium, acting as a net ion pump from lymph to plasma, with water following osmotically.

Mucosal Microvascular Organization of the Rat Colon

The mucosal microvascular architecture of the rat colon is described from vascular casts and intravital microscopy. Arterial break-up into the mucosal capillary bed invariably occurs at the submucosal/mucosal interface. The mucosal capillaries drain into venules only at the opposing, luminal aspect, i.e., mucosal venules transverse the mucosa without receiving further capillary tributaries. Intravital microscopy of luminal flow confirmed cast predictions. Further, capillary flow was unusually unidirectional, i.e., rarely static or reversible. The possible functional importance of this particular microvascular architecture to water absorption in the colon is discussed.

Changes in intrafollicular pressure in the rat ovary by nitric oxide and by alteration of systemic blood pressure.

BACKGROUND ovulation is associated with degradation of the follicular apex vasodilatation and increased permeability of ovarian vessels. These changes may maintain or increase intrafollicular pressure (IFP) at ovulation to cause rupture of the follicular wall. OBJECTIVE to investigate the possible regulation of IFP during the ovulatory process. STUDY DESIGN immature Sprague-Dawley rats were primed with pregnant mare serum gonadotrophin (PMSG; 10IU) and given hCG (10IU) 48h later. The ovary was exposed 48-60h after PMSG, micropipette inserted into the Graafian follicle and the IFP measured at three time periods: preovulatory (PO) 48h after PMSG; midovulatory (MO) 4-7h after hCG; late ovulatory (LO) 9-12h after hCG. The offset of the nitric oxide synthase (NOS) inhibitor L-arginine methyl ester (L-NAME), the alpha(1)-adrenoceptor agonist phenylephrine and the beta-adrenoceptor agonist isoprenaline were tested. RESULTS phenylephrine given i.v. increased the systemic blood pressure, and significantly decreased the IFP in the LO phase (78% of pre-treatment value). Local administration of phenylephrine or isoprenaline (1ml of 1.5-15 microM) by superfusion over the ovary did not change the IFP. Local administration of L-NAME (1ml of 2 microM) significantly lowered (P<0.05) the IFP in the MO and LO phases, but was without effect in the PO phase. CONCLUSION this study reveals that IFP regulation may be related to changes of the systemic blood pressure and that NO may be one local ovarian mediator in IFP regulation.

Vascular perfusability and capillary macromolecular permeability in the mechanically induced rabbit hydrosalpinx.

The mechanically induced rabbit hydrosalpinx, a frequently studied animal model of human hydrosalpinges, was examined to determine the variations, in vascular perfusion and capillary albumin permeability, which occur in hydrosalpinges. At laparotomy, 4 adult female virgin rabbits underwent isthmic and ampullary occlusion with small tantalum clips. 4 weeks later, fluorescein isothiocyanate-labelled bovine serum albumin (FITC BSA: molecular weight 67,000) was injected intravenously 5 min before oviduct excision. Examination of tubal sections by incident light fluorescent microscopy demonstrated poor interplical vascular perfusability and markedly reduced interplical capillary permeability to FITC BSA in both isthmic and ampullary segments of hydrosalpinx. These observations imply that, in the experimental rabbit hydrosalpinx, interplical deciliation is probably vascular in origin; furthermore the marked decrease in capillary macromolecule permeability may explain the serous fluid collection within the hydrosalpinx. Poor fecundity following microsurgical restoration of tubal patency in hydrosalpinges is possibly due to the failure of this decrease in submucosal capillary perfusability and macromolecular permeability to resolve.

Microvascular Architecture of the Pregnant Rabbit Oviduct

Methyl-methacrylate vascular corrosion casts of the oviducts were prepared in 7 rabbits which were 2-3 weeks pregnant. Scanning electron microscopy of the acrylic casts revealed little change in tubal microvascular connections when compared with control oviducts. Venous distension in the isthmic subserosal venous plexus, ampullary subserosal vasculature and in the fimbrial core was substantially greater than that observed in controls. These changes are interpreted as indicating a sensitivity of tubal microvasculature to the increased levels of circulating placental hormones in pregnancy. The implications of this interpretation in the role of tubal microvasculature at the time of ovulation are discussed.