A pilot study of skin stretching and blood circulation effects of dermal suctioning in dogs.

Dermal suctioning has been reported to yield effects similar to those of cupping therapy in humans and horses, including pain reduction, increased blood circulation, improved flexibility, and healing. However, there is a dearth of reported outcomes concerning cupping or dermal suctioning in dogs. In this study, we examined the physiological effects of dermal suctioning in dogs. Employing the Medicell MINI pro8 device, dermal suctioning was applied to the dorsal surfaces of eight healthy beagle dogs for 20 min. Metrics such as body surface temperature, rectal temperature, pulse rate, respiratory rate, and skin pinch test results were gauged. Seven healthy beagle dogs were used as controls, and the same measurements were performed without dermal suctioning. The results showed a significant increase in the body surface temperature and skin pinch test results after dermal suctioning. We believe that the elimination of torsion in the blood vessels and nerves in the shallow fascia positively affected the thermoregulatory mechanism, resulting in an increase in body surface temperature, and also improving skin flexibility. Thus, dermal suctioning promotes subcutaneous blood circulation and improves skin flexibility in dogs. Further research is needed to identify the mechanisms underlying the effects of dermal suctioning and evaluate the stress in dogs caused by the implementation of the process.

Changes in physiological parameters in healthy dogs on an underwater treadmill when the water level is set at the hip joint.

Understanding internal and external loading in exercise is important for safe rehabilitation. The physiological parameters of dogs have been studied in swimming, but those of dogs walking on an underwater treadmill have not been documented. In this study, four healthy beagle dogs were examined for changes in physiological parameters before and after walking in water for 20 min at a speed of 4 km/h with the water level set at the height of the hip joint as an external load. Statistical analysis of the results was performed using paired sample t-tests. Results indicated that heart rate (125 ± 11.8 beat/min to 163 ± 9.5 beat/min) and lactate levels (2 ± 0.1 mmol/L to 2.4 ± 0.2 mmol/ L) significantly increased from before to after walking on an underwater treadmill. Additional research is needed on internal loading when using underwater treadmills, which would further contribute to the safety of rehabilitation.

Effects of recombinant canine interferon-γ injected before general anesthesia with propofol and isoflurane on natural killer cytotoxic activity during anesthesia in dogs.

We aimed to determine whether subcutaneous injection of recombinant canine interferon-γ (rCaIFN-γ) 1h before general anesthesia with a combination of propofol and isoflurane (P-I) changes the cytotoxic activity of natural killer (NK) cells during anesthesia in dogs. Nine clinically healthy beagles were assigned to one of two groups: rCaIFN-γ-treated group (n=5) and control group (no treatment, n=4). One hour before P-I anesthesia, rCaIFN-γ was subcutaneously injected at a dose of 1×104U/kg body weight for the test group and physiologic saline was subcutaneously injected for the control group. Blood samples were collected 1h before P-I anesthesia (immediately before rCaIFN-γ injection) and 1 and 3h after anesthesia induction. NK cytotoxic activity was measured using the Rose Bengal assay, using canine thyroid adenocarcinoma cells as target cells. In the control group, NK cytotoxic activity decreased significantly over time (P<0.05). On the other hand, in the rCaIFN-γ group, the activity increased for the first hour after anesthesia induction without a significant difference from the level before anesthesia; furthermore, the activity at 3h after anesthesia induction was comparable with that before anesthesia. NK cytotoxic activity at 1 and 3h after anesthesia induction was significantly higher in the rCaIFNγ group than in the control group (P<0.05). Subcutaneous injection of rCaIFN-γ 1h before P-I general anesthesia not only maintained but also enhanced NK cytotoxic activity up to 3h after anesthesia induction in dogs. In conclusion, subcutaneous injection of rCaIFN-γ before cancer resection in cancer-bearing dogs might be effective for preventing intraoperative dissemination of cancer cells and postoperative cancer recurrence and metastasis.

Effect of rCaIFN-γ pretreatment on propofol-isoflurane suppression of NK cytotoxic activity in the peripheral blood of dogs.

In dogs, natural killer (NK) cell cytotoxic activity, which is an index of antitumor immunity, decreases after general anesthesia. In this study, we examined whether the decrease in NK cytotoxic activity can be controlled with interferon-gamma (IFN-γ) treatment. Beagles were divided into 2 groups: a treated group (n = 6) that received recombinant canine IFN-γ (rCaIFN-γ) and an untreated control group (n = 6). Blood samples were taken before and at 24, 120, and 192 hours after anesthesia. NK cytotoxic activity toward canine thyroid cancer cells was measured in isolated lymphocytes with the Rose Bengal assay. The decrease in NK cytotoxic activity after anesthesia was significantly inhibited by administration of rCaIFN-γ before propofol-isoflurane anesthesia. Further studies are necessary to evaluate the clinical implications of rCaIFN-γ treatment in tumor recurrence and morbidity.

Effect of rCaIFN-γ on NK cytotoxic activity in the peripheral blood of dogs.

Previously, the ability of interferon (IFN) to reinforce antitumor immune capacity has received much attention. In humans and mice, natural killer (NK) cells are activated by IFN, thereby reinforcing antitumor immunity. We investigated whether NK cytotoxic activity can be enhanced by recombinant canine interferon-gamma (rCaIFN-γ) in dogs. First, we investigated the effects of various concentrations of and time exposures to IFN-γ in the culture medium on the NK cytotoxic activity of peripheral blood lymphocyte (PBLs) extracted from healthy beagles. Time- and concentration-dependent enhancement of NK cytotoxic activity of PBLs was observed. We then investigated whether the NK cytotoxic activity of PBLs is enhanced 24h after administration of rCaIFN-γ (10,000 units/kg body weight) in healthy beagles. Our in vivo study confirmed that NK cytotoxic activity of PBLs was enhanced by this approach, suggesting that antitumor immunity was reinforced. In dogs, rCaIFN-γ may be effective for bolstering antitumor immune capacity.

Influence of general anesthesia with isoflurane following propofol-induction on natural killer cell cytotoxic activities of peripheral blood lymphocytes in dogs.

To investigate influence of general anesthesia on immunological anti-tumor activity, the natural killer (NK) cytotoxic activity of peripheral lymphocytes (PBLs) was measured in 7 dogs anesthetized for 3 hr with isoflurane following propofol-induction (anesthesia group) and 6 dogs without anesthesia (control group). Blood samples were collected before (baseline) and 24, 120 and 192 hr after the anesthesia. The PBLs were isolated via centrifugation with Ficoll-Hypaque solution (density, 1.073), and adherent cells were removed. The NK cytotoxic activity of the isolated PBLs against canine thyroid cancer cells was detected by the colorimetric rose Bengal assay. Significant decrease in the NK cytotoxic activity was observed at 24 hr after the anesthesia, compared with the baseline values and the control group. The NK cytotoxic activities were recovered to the baseline values until 120 hr after the anesthesia. The general anesthesia with isoflurane following propofol-induction decreased the NK cytotoxic activities of PBLs in dogs. This finding has a clinical relevance to the risk of tumor recurrence or metastasis induced by the suppression of immunological anti-tumor activity after general anesthesia in dogs. The results further emphasized the importance of the need to evaluate immune suppression following general anesthesia in animals.