Vascular branches from cutaneous nerve of the forearm and hand: Application to better understanding raynaud's disease.

Cutaneous nerves have branches called vascular branches (VBs) that reach arteries. VBs are thought to be involved in arterial constriction, and this is the rationale for periarterial sympathectomy as a treatment option for Raynaud's disease. However, the branching patterns and distribution areas of the VBs remain largely unclear. The aim of the present study was to investigate the anatomical structures of the VBs of the cutaneous nerves. Forty hands and forearms were examined to assess the branching patterns and distribution areas of the VBs of the superficial branch of the radial nerve (SBRN), the lateral antebrachial cutaneous nerve (LACN), the medial antebrachial cutaneous nerve (MACN), and the palmar cutaneous branch of the ulnar nerve (PCUN). VBs reaching the radial and ulnar arteries were observed in all specimens. The branching patterns were classified into six types. The mean distance between the radial styloid process and the point where the VBs reached the radial artery was 34.3 ± 4.8 mm in the SBRN and 38.5 ± 15.8 mm in the LACN. The mean distance between the ulnar styloid process and the point where the VBs reached the ulnar artery was 60.3 ± 25.9 mm in the MACN and 43.8 ± 26.0 mm in the PCUN. This study showed that the VBs of the cutaneous nerves have diverse branching patterns. The VBs of the SBRN had a more limited distribution areas than those of the other nerves. Clin. Anat. 31:734-741, 2018. © 2017 Wiley Periodicals, Inc.

Two-week cast immobilization induced chronic widespread hyperalgesia in rats.

It has been postulated that physical immobilization is an essential factor in developing chronic pain after trauma or surgery in an extremity. However, the mechanisms of sustained immobilization-induced chronic pain remain poorly understood. The present study, therefore, aimed to develop a rat model for chronic post-cast pain (CPCP) and to clarify the mechanism(s) underlying CPCP. To investigate the effects of cast immobilization on pain behaviours in rats, one hindlimb was immobilized for 2 weeks with a cast and remobilization was conducted for 10 weeks. Cast immobilization induced muscle atrophy and inflammatory changes in the immobilized hindlimb that began 2 h after cast removal and continued for 1 week. Spontaneous pain-related behaviours (licking and reduction in weight bearing) in the immobilized hindlimb were observed for 2 weeks, and widespread mechanical hyperalgesia in bilateral calves, hindpaws and tail all continued for 5-10 weeks after cast removal. A sciatic nerve block with lidocaine 24 h after cast removal transitorily abolished bilateral mechanical hyperalgesia in CPCP rats, suggesting that sensory inputs originating in the immobilized hindlimb contribute to the mechanism of both ipsilateral and contralateral hyperalgesia. Intraperitoneal injection of the free radical scavengers 4-hydroxy-2,2,6,6-tetramethylpiperydine-1-oxy1 or N-acetylcysteine 24 h after cast removal clearly inhibited mechanical hyperalgesia in bilateral calves and hindpaws in CPCP rats. These results suggest that cast immobilization induces ischaemia/reperfusion injury in the hindlimb and consequent production of oxygen free radicals, which may be involved in the mechanism of widespread hyperalgesia in CPCP rats.

Relationships among differentiated T-cell subpopulations. I. Dissociated development of tuberculin type hypersensitivity, Jones-Mote type hypersensitivity and activation of helper function.

Relationships among tuberculin type hypersensitivity, Jones-Mote type hypersensitivity and activation of helper T cells were studied in AKR mice by means of footpad reaction, migration inhibition test and antibody production against the trinitrophenyl group. (1) Immunization with SRBC in saline, Freund's incomplete adjuvant (FIA) or complete adjuvant (FCA) and fixed-SRBC (FRBC) in FIA- or FCA-induced delayed hypersensitivity as demonstrated by footpad swelling. (2) Migration inhibition was positive in the groups immunized with SRBC or FRBC in FCA, but negative in those immunized with SRBC in saline or FIA or FRBC in FIA. This may suggest that the former has to be assigned to tuberculin type and the latter to Jones-Mote type. (3) Both pre-treatment with BCG and with cyclophosphamide (CY) augmented delayed footpad reaction in the mice immunized with SRBC in saline. However, migration inhibition was positive only in the group pre-treated with BCG. BCG may convert the reaction from Jones-Mote type to tuberculin type, while CY may augment the reaction of Jones-Mote type. (4) FRBC in saline scarcely induced delayed footpad reaction, whereas they activated helper function efficiently. Thus, three types of immunological phenomena attributable to the functions of T cells may depend upon distinct subpopulations of differentiated T cells which are raised by different methods of immunization.