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In tetrapods, limb and axial movements are coordinated during locomotion. It is well established that inter- and intralimb coordination show considerable variations during ongoing locomotion. Much less is known about the flexibility of the axial musculoskeletal system during locomotion and the neural mechanisms involved. Here we examined this issue in the salamander Pleurodeles waltlii, which is capable of locomotion in both aquatic and terrestrial environments. Kinematics of the trunk and electromyograms from the mid-trunk epaxial myotomes were recorded during four locomotor behaviors in freely moving animals. A similar approach was used during rhythmic struggling movements since this would give some insight into the flexibility of the axial motor system. Our results show that each of the forms of locomotion and the struggling behavior is characterized by a distinct combination of mid-trunk motor patterns and cycle durations. Using in vitro electrophysiological recordings in isolated spinal cords, we observed that the spinal networks activated with bath-applied N-methyl-d-aspartate could generate these axial motor patterns. In these isolated spinal cord preparations, the limb motor nerve activities were coordinated with each mid-trunk motor pattern. Furthermore, isolated mid-trunk spinal cords and hemicords could generate the mid-trunk motor patterns. This indicates that each side of the cord comprises a network able to generate coordinated axial motor activity. The roles of descending and sensory inputs in the behavior-related changes in axial motor coordination are discussed.

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Skin patches of a clonidine transdermal therapeutic system (clonidine-TTS) with a constant release rate of either 0.1 or 0.2 mg clonidine/24 h continuously over 7 days were used in 32 essential hypertensives. These self-adhesive drug delivery systems (3.5 cm2), which were affixed to the upper outer arm, were changed by the patients at weekly intervals. During a mean observation period of 7 months (range 1-19 months) transdermal clonidine reduced the blood pressure from 162 +/- 15/107 +/- 5 mmHg to normal values (diastolic less than or equal to 95 mmHg) in 63% of our patients. However, chronic use of clonidine-TTS was accompanied by a high frequency of contact dermatitis (type IV allergy) in nearly half of our patients (n = 15, 47%). In 11 of these 15 patients transdermal clonidine administration had to be stopped because of intolerable local skin reactions (pruritus, erythema, vesiculation, and/or infiltration). Subsequent patch testing with all components of clonidine-TTS was performed in eight cases. Whereas in seven cases an allergic contact dermatitis to clonidine was found, only one patient showed an allergy to another component of clonidine-TTS (polyisobutylene). We conclude that this strikingly high incidence of local allergic skin reactions limits the use of clonidine-TTS in essential hypertension.

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The antihypertensive efficacy and side effects of a transdermal therapeutic system containing 2.5 mg clonidine (clonidine-TTS) was investigated in 21 patients with essential hypertension over a period of 10 weeks. The system was designed to release 0.1 mg clonidine/24 h. Mean systolic and diastolic blood pressure fell from 160 +/- 17/106 +/- 7 mm Hg to 139 +/- 16/91 +/- 8 mm Hg after 4 weeks and to 135 +/- 14/89 +/- 8 mm Hg after 10 weeks (p less than 0.001). Sufficient blood pressure control was achieved by one clonidine-TTS weekly in 24% and by 2 clonidine-TTS in 33% of the patients. 43% of all cases required additional oral therapy with 50 mg hydrochlorothiazide/day. However, antihypertensive action was accompanied by a high incidence of local skin reactions. These skin reactions with erythema, itching and red papules occurred in 6 of the 21 patients (29%) after treatment with TTS for at least 4 weeks. Patch testing with the various components of clonidine-TTS in 4 patients identified clonidine-allergy of delayed type in 3 cases. Typical clonidine side effects such as fatigue, dry mouth, constipation and sexual disturbances were moderate. It is concluded that clonidine-TTS has a good and continuous antihypertensive action. However, the high incidence of skin reactions limits its use in the treatment of essential hypertension.

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The antihypertensive effects and side-effects of a clonidine transdermal therapeutic system (clonidine-TTS) were examined over 10 weeks in 22 patients with essential hypertension. The clonidine-TTS containing a 2.5 mg drug reservoir was designed to release 0.1 mg clonidine/24 h for seven days through a micropore rate-controlling membrane. In the total group mean systolic and diastolic blood pressure decreased from 162 +/- 14/106 +/- 4 mmHg to 137 +/- 17/92 +/- 8 mmHg after four weeks and 136 +/- 13/90 +/- 7 mmHg after 10 weeks (P less than 0.001). Five patients (23%) responded well to one clonidine-TTS (diastolic blood pressure less than or equal to 95 mmHg) and seven patients (32%) needed two clonidine-TTS. Additional oral therapy with 50 mg hydrochlorothiazide/day resulted in reduction of blood pressure to normal in six of the remaining 10 patients. This good pressure response was, however, accompanied by a high incidence of local allergic skin reactions of delayed type (type IV) in seven (32%) of the 22 cases. Patch testing with various components of clonidine-TTS which was performed in four of the seven patients showed in three cases allergic contact dermatitis to clonidine. Our results demonstrate a good and sustained antihypertensive action of clonidine-TTS. However, the extraordinarily high incidence of skin allergy to clonidine limits its use in the treatment of essential hypertension.

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The authors report 7 cases of allergic respiratory diseases such as asthma, allergic rhinitis and bronchitis, induced by non-occupational contact with pet-fish food. Food for pet fish contains proteins of a variety of arthropod species (larvae and adult forms) --e.g. Chironomus, Daphnia, brine shrimps and others --as well as fresh-water worms such as Tubifex, Enchytraea etc. Thus far only hemoglobins of Chironomus have been well studied with regard to their antigenic role; sensitization against Chironomus was noticed in most of our patients. Daphnia is also known to be a specific allergen. Atopic patients often become sensitized against further respiratory allergens (5 out of the 7 patients had a previous allergy against pollen). Accordingly, patients with respiratory diseases of already known allergic origin should, in our opinion, give up not only mammals or birds as household pets but also an aquarium.

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