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The effects of the sampling season of explants and the growth stage of mother plants on the regenerative capacity and growth characteristics of regenerants in the shoot apex culture of chrysanthemums were investigated. Shoot apices from two edible cultivars of the autumn-flowering type, 'Abokyu' and 'Enmeiraku', were cultured for three months on a modified Shizuoka Agricultural Experiment Station medium supplemented with NAA (1 mg·liter-1). Every two or three weeks from April to September 1991, shoot apices were collected from the terminal and axillary buds of non-pinching plants and cultured. The regeneration rate varied with the cultivars used and the sampling season. When the terminal buds of primary lateral shoots that developed after pinching were cultured, high percentages of regenerants were obtained from vigorously growing mother plants in both cultivars. Even in the early reproductive growth phase (involucre- formation stage), the explants maintained some regenerative capacity. The growth characteristics of regenerants differed with the cultivars used and the growth stages of the mother plants.

To elucidate the usefulness of the small-flowered chrysanthemum, 'YS', which has the smallest chromosome number (2n=36) among parental breeding materials, the characteristics of progenies derived from 'YS' crosses with hexaploid (2n=54) cultivars were investigated. Our histological observations on the developmental process of the anther showed that the tapetum did not dehisce at the mature pollen stage. Therefore, we regard 'YS' as one example of male sterility. Cross pollinations between 'YS' or its polyploid (2n=72) with three hexaploid cultivars (2n=54) yielded a number of seeds per inflorescence, but their percentage of germination differed with cross combinations. Examinations of the F1 progenies revealed that most progenies grew vigorously, and their mean height exceeded the intermediate value of their parents. Flower types that were classified according to the morphology of the capitulum showed that the progenies between 'YS' (petaloidy-type) × three cultivars (nonpetaloidy-type) were characteristic of the male parent type. The diameters of inflorescences in the progenies derived from 'YS' (small-type) × three cultivars (medium-type) were about 10% smaller than the intermediate value of their parents, whereas their pollen fertilities were: 'YS' (5.3%), its polyploid (43%), and the three cultivars (78.6- 83.1%), similar to their male parents. The progenies derived from 'YS' (male-sterile) × three cultivars (male-fertile) were all male-fertile. The chromosome numbers in the progenies between 'YS' (2n=36) × three cultivars (2n=54) were most frequently pentaploid (2n=45), intermediate between the parents. The stability of the heritable characteristics of progenies over four years showed that although it differed between years and crosses, variable characteristics were plant height, plant form and flowering times, whereas the stable characteristics were their growth appearance, diameter of inflorescence and flower types. The most stable characteristic was flower color. From this study, we considered that 'YS' poses no problem to use as a female parent in crosses between cultivars whose chromosome numbers differ significantly.

Interspecific hybrids between Allium fistulosum L. (2n=16) and A. schoenoprasum L. (2n=16) which are classified to different sections of the Allium were investigated cytogenetically to elucidate their relationship. Hybrid plants (2n=16) were produced by reciprocal crossings through embryo or ovule cultures, but the number of hybrid plants derived per pollinated flower was much smaller in the combination using A. fistulosum as a seed parent. At meiotic metaphase-I, chromosome parings of 161 or 1II+14I occurred frequently ; tetrads were observed together with dyads and heptads at tetrad stage. The hybrid plants exhibited three types of anther development ; a) fully developed form, b) aborted form or c) having both forms. Unreduced spherical pollen grains were observed in fully developed anthers. Pollen stainability ranged from 13 to 65%. No plant was obtained in the backcross with A. fistulosum. Chromosome doubled plants were produced through colchcine treatment of hybrid plants. In the chromosome doubled plant derived from the hybrid plant with fully developed anthers, pollen stainability was 64%. No seed was obtained through open pollination and crossing with A. fistulosum as a pollen parent. In the chromosome doubled plant derived from the hybrid plant with aborted anthers, anthers were aborted and were pollen-sterile. These results indicate that the homology between the genomes of A. fistulosum and A. schoenoprasum is low and that they are distantly related to each other cytogenetically.

In order to improve the plating efficiency on spinach mesophyll protoplast culture, various conditions were examined with four cvs. of spinach, four cvs. of chard and one cv. of tablebeet. 1. Mesophyll protoplasts of these test plants were isolated from the in vitro-grown young seedlings by treatment of the enzyme solution containing 2 % Cellulase Onozuka RS, 0.5 % Cellulase Onozuka R-10,0.5 % Macerozyme R-10,0.02 % Pectolyase Y-23,CPW salts, 0.1 % MES and 0.5 M sorbitol (pH 5.8) for 4-11 hours. 2. The cell division and colony formation of spinach cv. 'SHINNIPPON' occurred only in a modified MS medium (No. 3) containing 1 mg/l NAA, 1 mg/l 2,4-D and 1 mg/l BA in five combinations of growth regulators. 3. The cell division and colony formation of protoplasts only occurred in all spinach cvs., but not in chard and tablebeet in No. 3 medium. 4. The frequency of cell division and colony formation in spinach cv. 'F_1 SHINRYOKU' increased to DMSO concentration. Plating efficiency of the medium containing 1.0 % DMSO (14.7 %) was much higher than that of the medium without DMSO (3.2 %) . 5. We now plan to induce plant regeneration from the thus obtained callus.

We found indomethacin aggravates healed gastric ulcers (ulcer relapse) in rats. In the present study, we examined the effects of human basic fibroblast growth factor (bFGF) mutein CS23 (TGP-580) and histamine H2-receptor antagonists (H2-RAs) on ulcer relapse in this model. In male SD rats, gastric ulcers were induced in the antrum by injection of acetic acid. Indomethacin (1 mg/kg/day) given s.c. for 2 weeks starting 4 weeks after the operation aggravated the healed ulcer; the areas with and without indomethacin were 4.8 +/- 1.4 and 0.4 +/- 0.3 mm2, respectively. Drugs were given orally once daily for 4 weeks starting 2 days after the operation or for the 2-week indomethacin administration period. Treatment with ranitidine (100 mg/kg), cimetidine (100 mg/kg) and TGP-580 (0.1 mg/kg) for 4 weeks accelerated the healing. The aggravation by indomethacin was significantly inhibited by pretreatment with TGP-580 and mildly inhibited by cimetidine but not ranitidine. When the drugs were co-administered with indomethacin for 2 weeks, the aggravation was significantly prevented by ranitidine and mildly inhibited by cimetidine and TGP-580. Both TGP-580 and H2-RAs can prevent the ulcer relapse induced by indomethacin but via different modes of action: TGP-580 inhibits relapse mainly by acting on the process of healing, while H2-RAs act mainly on the process of aggravation.

Lansoprazole, a proton pump inhibitor, exerts prominent antiulcer activity via both antisecretory and mucosal protective actions. Although the antisecretory action has been explained by inactivation of (H+, K+)-ATPase in parietal cells, the mode of mucosal protective action remains to be elucidated. In the present study, the effect of lansoprazole on duodenal bicarbonate secretion was studied in anesthetized rats to clarify the mode of the mucosal protective action. Lansoprazole (0.1 mM) applied topically to the duodenum significantly (P < 0.01) increased bicarbonate secretion by 0.36 +/- 0.11 microeq/15 min (21 +/- 5%) compared with the value in the vehicle control. Topical administration of capsaicin (10 mg/ml) in the duodenum and intravenous infusion of vasoactive intestinal peptide (10 micrograms/kg/hr) increased bicarbonate secretion. Five-minute perfusion of the duodenal loop with 100 mM HCl increased bicarbonate secretion. Administration of lansoprazole (0.3 and 1 mg/kg, intravenously) 60 min before luminal acidification enhanced the acid-induced bicarbonate secretion dose-dependently and significantly (P < 0.01). In the capsaicin-pretreated rats, the effects of lansoprazole on basal and acid-induced bicarbonate secretion were significantly (P < 0.05) decreased compared with that of control group. These results indicate that lansoprazole increases basal and acid-induced bicarbonate secretion in the duodenum in rats and that capsaicin-sensitive sensory neurons may be involved in the mode of action for these effects.

C-banded karyotypes and their variations were studied in Allium fistulosum and A. altaicum, and the phylogenetic relationship between the two species was verified.1. All plants of cultivars and strains examined in A. fistulosum had the same karyotypes except for a variation of satellites [K(2n) =14V+2JT, 14V+1JT+1Jt, 14V+1JT+1J]. The telomeric and centromeric regions in all chromosomes, satellites and proximal regions to the nucleolar organizer in No. 6 chromosome, and five intercalary regions in No. 6, 7, 8 chromosomes were differentially stained as the fundamental C-banding pattern of A. fistulosum.2. Two strains of A. altaicum were, in whole, similar to A. fistulosum in the karyotype, including the variation of satellites. The C-banding patterns differed between the two species by the presence or absence of three intercalary bands.3. In F1 hybrid plants between A. fistulosum and A. altaicum, the somatic chromosome complement consisted of eight pairs of chromosomes after C-banded karyotype analysis. Almost homologous meioses in PMCs were observed in F1 hybrid plants. Moreover, F1 hybrid plants showed high seed fertility. Consequently, these results suggest that A. fistulosum and A. altaicum have homologous genomes, and indicate the degree of their close relationship.

To elucidate the basis of chromosome variations in the Japanese garden chrysanthemum, the present study was carried out using natural sports in flower colour.1. Of 297 chrysanthemum cultivars examined, we found the frequency of sports to be low and varied slightly among the flowering forms. The average mutation frequency within this select group was 10.8%; it ranged from 5.2 to 15.7%.2. Thirty-two sports and 25 parental cultivars of Japanese chrysanthemums were surveyed for chromosome number variations. The chromosome numbers in 5 out of 32 sports (15.6%) differed from the parents by plus or minus one chromosome.3. Several clonal strains of 'Kii-amaga-hara' and their parental cultivar 'Amaga-hara' from which they originated as sports were subjected to karyotype analysis as related to satellite chromosome variations. The chromosome numbers varied little in the sport or parental plants, whereas the karyotype constitutions differed considerably among them. These results indicate that structural changes in chromosomes may have occurred in the sports.4. Four clonal strains of 'Kii-shuho-no-chikara' and five of its parental cultivar 'Shuho-no-chikara' were examined for the variations in chromosome numbers and certain morphological or ecological characteristics. Four parental strains (80% of those examined) had the same chromosome number (2n=54) as the original clone but in the two mutant strains (50% of those examined), the chromosome number was 52. As one might expect, the loss of two chromosomes by the strains resulted in considerable differences in several characteristics as compared with the original clone.5. Our analysis confirms that the appearance of sports is attributable to chromosome variations in the garden chrysanthemums. However, the frequency of these sports depends on the particular cultivar of chrysanthemum.

To elucidate the karyomorphological character and mechanism of the appearance of aneuploidy in garden chrysanthemums, karyotype analysis was made by using 17 cultivars and one strain of chrysanthemum which differ in use, flower size, and flower type.1. Size and shape of chromosomes. 1) The longest chromosome in each cultivar was 3.95.8 μm (av. 4.9 μm) and the shortest was 1.73.3 μm (av. 2.6μm). 2) The shape was classified into four types by the position of centromere; medium (m), sub-median (sm), subterminal (st), and terminal (t). Since the morphological variation of chromosomes was narrow, it was difficult to detect an indicator chromosome. 3) One to seven satellite chromosomes per chromosome set were observed in 77.8% of given cultivars; usually one to four and rarely were there five to seven.2. As for the position of centromere, most chromosomes were the m type, followed by sm, st, and t types. A possible relationship between the frequency of occurrence of the m type chromosomes and use or flower size of garden chrysanthemum was recognizable in some cases. The karyotype component of garden chrysanthemums showed obvious hybridity in all cultivars.3. Judging from the above results, the heterozygous karyotype seems to be closely related to the occurrence of aneuploidy in garden chrysanthemums. Moreover, the genomic makeup of the aneuploidy differed among the cultivars of garden chrysanthemum.

1. A survey of chromosome numbers of edible (Shokuyo-giku) and garnish (Tsuma-giku) chrysanthemum was carried out to elucidate the genetic characteristics and varietal differentiation in those cultivars. Cultivars of edible (137) and garnish (32) chrysanthemums were examined for this study.2. Examination of entire plants revealed variations in somatic chromosome numbers ranging from 53 to 66 in edible chrysanthemums and from 51+B to 55 in garnich forms. Furthermore, the mode of the distribution in chromosome numbers was 54 for both edible and garnish forms. Variation frequency of chromosome number in both forms agreed well with that of ornamental chrysanthemums. Therefore, according to chromosome variation, edible and garnish chrysanthemums were duly considered to have been derived from ornamental cultivars grown for exhibition or cut-flower use.3. Different number of chromosomes were observed among root tip cells within the same individual. A similar chromosomal variation was found between individual plants or clones of the same cultivar, some cells possessing 54±1, 2, or 3 chromosomes.4. B chromosomes were recognized in both forms of chrysanthemums.5. This investigation revealed confusion in nomenclature; for example, among 26 cultivars examined, some had 2 to 9 synonyms. Therefore, the actual number of edible chrysanthemum cultivars was 65, and that of garnish forms was 30.6. Correlations between chromosme number and flowering period or flower size were ascertained among edible chrysanthemums.

Indomethacin produces gastric corpus erosions in the fasted rat and small intestinal ulcers in the conventionally fed rat. We found that in rats fed chow pellets for 1 h after a 24-h fast, indomethacin given within 2 h after refeeding produced lesions in the gastric antrum, primarily along the lesser curvature, and also in the small intestine. The antral lesions reached a maximum size in 6–10 h, penetrated the muscularis mucosae within 3 days, and did not diminish for at least 7 days. The formation of the antral ulcer was prevented by prostaglandins or adrenalectomy, but was not affected by cimetidine, atropine, and/or vagotomy. In contrast, the gastric corpus erosions produced by indomethacin in the fasted rat were prevented by antisecretory drugs or vagotomy, and were aggravated by adrenalectomy. It is concluded that: (a) the chronic antral ulcers produced by indomethacin in the refed rat mimic human gastric ulcer with regard to location and histology; and (b) the mechanism of antral ulcer formation is different from corpus erosion formation, in that it was resistant to antisecretory drugs and vagotomy and was prevented by adrenalectomy. This experimental ulcer model could prove useful for studies of the etiology and therapy of gastric ulcer disease.

A chromatographic study of methanol-soluble leaf extracts was undertaken to analize the phylogenetic relationships between a number of species, vavieties and cultivars in Brassica and its allied genera.Raphanus sativus (genome constitution; RR), 9 out of 18 detected spots in this species being quite specific, was remarkably different in its characteristic spot pattern from three diploid species of Brassica and Sinapis arvensis. Accordingly, it was clearly indicated in the chromatogram on the occurrence of two genome-specific spot groups originating from both parental species that Raphano-brassica was composed of R. sativus and B. oleracea.B. campestris (AA), B. nigra (BB), B. oleracea(CC) and S. arvensis (SS) could be determined from each other by their genome-specific spot patterns, though many kinds of spots detected usually occur throughout those species. Because of the similarities of spot constitution in the diploid Brassica species, the spot patterns of three amphidiploids Brassica species (AABB, AACC and BBCC), natural or artificial, could not be revealed as a complete complementation of the spot groups of the diploid ancestral species.Based on peculiar spot patterns on the chromatograms, cultivars examined within B. campestris or B. oleracea could be distinguished from each other in some minor points, but the intraspecific variations of spot patterns did not correlate with taxonomic rank.Good numerical information of the phylogenetic affinities between and among the taxa analized could be obtained by the application of the concepts of paired affinity and grouped affinity (Ellison et al., 1962) to the results of the present study. Referring to the affinity values it will be noted that : R. sativus generally shows the lowest affinity to all other species used. S. arvensis is closer to B. nigra than to the other species used. The highest degree of affinity is obtained between B. campestris and B. oleracea, and B. nigra shows a higher affinity to B. campestris than to B. oleracea.

The protective effect of spizofurone (AG-629) on the rat gastric mucosa was studied in the presence of various stimuli. Spizofurone given orally markedly inhibited gastric lesions induced by ethanol (ED 50 = 6.5 mg/kg). Spizofurone inhibited ethanol-induced gastric lesions even when administered intraperitoneally (i.p.), but the onset of action after oral administration was shorter. Spizofurone given orally or i.p. in a dose range of 25–200 mg/kg inhibited indomethacin-induced gastric antral ulcers in re-fed rats. Furthermore, spizofurone potentiated the inhibitory effect of prostaglandin E 2 on indomethacin-induced gastric antral ulcers. Spizofurone given i.p. prevented a decrease in potential difference and the formation of gastric lesions induced by intragastric instillation of 30 mM aspirin in 0.1 N HCl. Spizofurone given i.p. inhibited the increase in net fluxes of H + and Na + caused by intragastric instillation of 15% ethanol in 0.1 N HCl. These findings indicate that spizofurone, like prostaglandin E 2 , exerts gastric mucosal protection and even potentiates the anti-ulcer effect of prostaglandin E 2 . The gastric mucosal protection by spizofurone is ascribed in part to preservation of the mucosal barrier.

The effect of spizofurone, a new anti-ulcer agent, on alkaline secretion was studied in an isolated sheet of bullfrog proximal duodenal mucosa mounted in an Ussing chamber. Spizofurone (10−4-10−3 M) as well as prostaglandin E2 (PGE2, 10−8-10−5 M) added to the nutrient solution increased alkaline secretion, transmucosal potential difference (PD) and short-circuit current (Isc), in a concentration-dependent manner. The maximum increases in alkaline secretion stimulated by spizofurone and PGE2 were much the same. Spizofurone also showed this effect when added to the secretory solution while PGE2 did not. Treatment with indomethacin partly but significantly inhibited the effect of spizofurone, but did not affect that of PGE2. These results indicate that the increase in alkaline secretion in bullfrog duodenal mucosa seen in the presence of spizofurone is mediated, at least in part, by stimulation of endogenous PGs synthesis.